Difference between revisions of "IMO Problems and Solutions"

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* [[1959 IMO]] (in Romania)
 
* [[1959 IMO]] (in Romania)
* [[1959 IMO Problems]]
 
 
* [[1959 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1959 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1959 IMO Problems/Problem 2 | Problem 2]] proposed by Constantin Ionescu-Tiu, Romania
 
* [[1959 IMO Problems/Problem 2 | Problem 2]] proposed by Constantin Ionescu-Tiu, Romania
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* [[1960 IMO]] (in Romania)
 
* [[1960 IMO]] (in Romania)
* [[1960 IMO Problems]]
 
 
* [[1960 IMO Problems/Problem 1 | Problem 1]] proposed by Bulgaria
 
* [[1960 IMO Problems/Problem 1 | Problem 1]] proposed by Bulgaria
 
* [[1960 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
 
* [[1960 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
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* [[1961 IMO]] (in Hungary)
 
* [[1961 IMO]] (in Hungary)
* [[1961 IMO Problems]]
 
 
* [[1961 IMO Problems/Problem 1 | Problem 1]] proposed by Hungary
 
* [[1961 IMO Problems/Problem 1 | Problem 1]] proposed by Hungary
 
* [[1961 IMO Problems/Problem 2 | Problem 2]] proposed by Poland
 
* [[1961 IMO Problems/Problem 2 | Problem 2]] proposed by Poland
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* [[1962 IMO]] (in Czechoslovakia)
 
* [[1962 IMO]] (in Czechoslovakia)
* [[1962 IMO Problems]]
 
 
* [[1962 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1962 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1962 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
 
* [[1962 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
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* [[1963 IMO]] (in Poland)
 
* [[1963 IMO]] (in Poland)
* [[1963 IMO Problems]]
 
 
* [[1963 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1963 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1963 IMO Problems/Problem 2 | Problem 2]] proposed by USSR
 
* [[1963 IMO Problems/Problem 2 | Problem 2]] proposed by USSR
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* [[1964 IMO]] (in USSR)
 
* [[1964 IMO]] (in USSR)
* [[1964 IMO Problems]]
 
 
* [[1964 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1964 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1964 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
 
* [[1964 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
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* [[1965 IMO]] (in East Germany)
 
* [[1965 IMO]] (in East Germany)
* [[1965 IMO Problems]]
 
 
* [[1965 IMO Problems/Problem 1 | Problem 1]] proposed by Yugoslavia
 
* [[1965 IMO Problems/Problem 1 | Problem 1]] proposed by Yugoslavia
 
* [[1965 IMO Problems/Problem 2 | Problem 2]] proposed by Poland
 
* [[1965 IMO Problems/Problem 2 | Problem 2]] proposed by Poland
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* [[1966 IMO]] (in Bulgaria)
 
* [[1966 IMO]] (in Bulgaria)
* [[1966 IMO Problems]]
 
 
* [[1966 IMO Problems/Problem 1 | Problem 1]] proposed by USSR
 
* [[1966 IMO Problems/Problem 1 | Problem 1]] proposed by USSR
 
* [[1966 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
 
* [[1966 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
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* [[1967 IMO]] (in Yugoslavia)
 
* [[1967 IMO]] (in Yugoslavia)
* [[1967 IMO Problems]]
 
 
* [[1967 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1967 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1967 IMO Problems/Problem 2 | Problem 2]] proposed by Czechoslovakia
 
* [[1967 IMO Problems/Problem 2 | Problem 2]] proposed by Czechoslovakia
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* [[1968 IMO]] (in USSR)
 
* [[1968 IMO]] (in USSR)
* [[1968 IMO Problems]]
 
 
* [[1968 IMO Problems/Problem 1 | Problem 1]] proposed by Unknown Author, Romania (taken from a Romanian problem book)
 
* [[1968 IMO Problems/Problem 1 | Problem 1]] proposed by Unknown Author, Romania (taken from a Romanian problem book)
 
* [[1968 IMO Problems/Problem 2 | Problem 2]] proposed by Czechoslovakia
 
* [[1968 IMO Problems/Problem 2 | Problem 2]] proposed by Czechoslovakia
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* [[1969 IMO]] (in Romania)
 
* [[1969 IMO]] (in Romania)
* [[1969 IMO Problems]]
 
 
* [[1969 IMO Problems/Problem 1 | Problem 1]] proposed by Wolfgang Engel, East Germany
 
* [[1969 IMO Problems/Problem 1 | Problem 1]] proposed by Wolfgang Engel, East Germany
 
* [[1969 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
 
* [[1969 IMO Problems/Problem 2 | Problem 2]] proposed by Hungary
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* [[1970 IMO]] (in Hungary)
 
* [[1970 IMO]] (in Hungary)
* [[1970 IMO Problems]]
 
 
* [[1970 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1970 IMO Problems/Problem 1 | Problem 1]] proposed by Poland
 
* [[1970 IMO Problems/Problem 2 | Problem 2]] proposed by Dumitru Batinetzu, Romania
 
* [[1970 IMO Problems/Problem 2 | Problem 2]] proposed by Dumitru Batinetzu, Romania
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* [[1971 IMO]] (in Czechoslovakia)
 
* [[1971 IMO]] (in Czechoslovakia)
* [[1971 IMO Problems]]
 
 
* [[1971 IMO Problems/Problem 1 | Problem 1]] proposed by Hungary
 
* [[1971 IMO Problems/Problem 1 | Problem 1]] proposed by Hungary
 
* [[1971 IMO Problems/Problem 2 | Problem 2]] proposed by USSR
 
* [[1971 IMO Problems/Problem 2 | Problem 2]] proposed by USSR
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* [[1972 IMO]] (in Poland)
 
* [[1972 IMO]] (in Poland)
* [[1972 IMO Problems]]
 
 
* [[1972 IMO Problems/Problem 1 | Problem 1]] proposed by USSR
 
* [[1972 IMO Problems/Problem 1 | Problem 1]] proposed by USSR
 
* [[1972 IMO Problems/Problem 2 | Problem 2]] proposed by Netherlands
 
* [[1972 IMO Problems/Problem 2 | Problem 2]] proposed by Netherlands
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* [[1973 IMO]] (in USSR)
 
* [[1973 IMO]] (in USSR)
* [[1973 IMO Problems]]
 
 
* [[1973 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1973 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1973 IMO Problems/Problem 2 | Problem 2]] proposed by Poland
 
* [[1973 IMO Problems/Problem 2 | Problem 2]] proposed by Poland
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* [[1974 IMO]] (in East Germany)
 
* [[1974 IMO]] (in East Germany)
* [[1974 IMO Problems]]
 
 
* [[1974 IMO Problems/Problem 1 | Problem 1]] proposed by Murray Klamkin, USA
 
* [[1974 IMO Problems/Problem 1 | Problem 1]] proposed by Murray Klamkin, USA
 
* [[1974 IMO Problems/Problem 2 | Problem 2]] proposed by Matti Lehtinen, Finland
 
* [[1974 IMO Problems/Problem 2 | Problem 2]] proposed by Matti Lehtinen, Finland
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* [[1975 IMO]] (in Bulgaria)
 
* [[1975 IMO]] (in Bulgaria)
* [[1975 IMO Problems]]
 
 
* [[1975 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1975 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1975 IMO Problems/Problem 2 | Problem 2]] proposed by United Kingdom
 
* [[1975 IMO Problems/Problem 2 | Problem 2]] proposed by United Kingdom
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* [[1976 IMO]] (in Austria)
 
* [[1976 IMO]] (in Austria)
* [[1976 IMO Problems]]
 
 
* [[1976 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1976 IMO Problems/Problem 1 | Problem 1]] proposed by Czechoslovakia
 
* [[1976 IMO Problems/Problem 2 | Problem 2]] proposed by Matti Lehtinen, Finland
 
* [[1976 IMO Problems/Problem 2 | Problem 2]] proposed by Matti Lehtinen, Finland
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* [[1977 IMO]] (in Yugoslavia)
 
* [[1977 IMO]] (in Yugoslavia)
* [[1977 IMO Problems]]
 
 
* [[1977 IMO Problems/Problem 1 | Problem 1]] proposed by Jan van de Craats, Netherlands
 
* [[1977 IMO Problems/Problem 1 | Problem 1]] proposed by Jan van de Craats, Netherlands
 
* [[1977 IMO Problems/Problem 2 | Problem 2]] proposed by Phan Duc Chinh, Vietnam
 
* [[1977 IMO Problems/Problem 2 | Problem 2]] proposed by Phan Duc Chinh, Vietnam
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* [[1978 IMO]] (in Romania)
 
* [[1978 IMO]] (in Romania)
* [[1978 IMO Problems]]
 
 
* [[1978 IMO Problems/Problem 1 | Problem 1]] proposed by Cuba
 
* [[1978 IMO Problems/Problem 1 | Problem 1]] proposed by Cuba
 
* [[1978 IMO Problems/Problem 2 | Problem 2]] proposed by Murray Klamkin, USA
 
* [[1978 IMO Problems/Problem 2 | Problem 2]] proposed by Murray Klamkin, USA
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* [[1979 IMO]] (in United Kingdom)
 
* [[1979 IMO]] (in United Kingdom)
* [[1979 IMO Problems]]
 
 
* [[1979 IMO Problems/Problem 1 | Problem 1]] proposed by Arthur Engel, West Germany
 
* [[1979 IMO Problems/Problem 1 | Problem 1]] proposed by Arthur Engel, West Germany
 
* [[1979 IMO Problems/Problem 2 | Problem 2]] proposed by Nickolay Khadzhiivanov and Nedjalko Nenov, Bulgaria
 
* [[1979 IMO Problems/Problem 2 | Problem 2]] proposed by Nickolay Khadzhiivanov and Nedjalko Nenov, Bulgaria
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* [[1981 IMO]] (in USA)
 
* [[1981 IMO]] (in USA)
* [[1981 IMO Problems]]
 
 
* [[1981 IMO Problems/Problem 1 | Problem 1]] proposed by David Monk, United Kingdom
 
* [[1981 IMO Problems/Problem 1 | Problem 1]] proposed by David Monk, United Kingdom
 
* [[1981 IMO Problems/Problem 2 | Problem 2]] proposed by Arthur Engel, West Germany
 
* [[1981 IMO Problems/Problem 2 | Problem 2]] proposed by Arthur Engel, West Germany
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* [[1982 IMO]] (in Hungary)
 
* [[1982 IMO]] (in Hungary)
* [[1982 IMO Problems]]
 
 
* [[1982 IMO Problems/Problem 1 | Problem 1]] proposed by David Monk, United Kingdom
 
* [[1982 IMO Problems/Problem 1 | Problem 1]] proposed by David Monk, United Kingdom
 
* [[1982 IMO Problems/Problem 2 | Problem 2]] proposed by Jan van de Craats, Netherlands
 
* [[1982 IMO Problems/Problem 2 | Problem 2]] proposed by Jan van de Craats, Netherlands
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* [[1983 IMO]] (in France)
 
* [[1983 IMO]] (in France)
* [[1983 IMO Problems]]
 
 
* [[1983 IMO Problems/Problem 1 | Problem 1]] proposed by David Monk, United Kingdom
 
* [[1983 IMO Problems/Problem 1 | Problem 1]] proposed by David Monk, United Kingdom
 
* [[1983 IMO Problems/Problem 2 | Problem 2]] proposed by Igor F. Sharygin, USSR
 
* [[1983 IMO Problems/Problem 2 | Problem 2]] proposed by Igor F. Sharygin, USSR
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* [[1984 IMO]] (in Czechoslovakia)
 
* [[1984 IMO]] (in Czechoslovakia)
* [[1984 IMO Problems]]
 
 
* [[1984 IMO Problems/Problem 1 | Problem 1]] proposed by Michael Stoll and Bruno Haible, West Germany
 
* [[1984 IMO Problems/Problem 1 | Problem 1]] proposed by Michael Stoll and Bruno Haible, West Germany
 
* [[1984 IMO Problems/Problem 2 | Problem 2]] proposed by Aiko Tiggelaar, Netherlands
 
* [[1984 IMO Problems/Problem 2 | Problem 2]] proposed by Aiko Tiggelaar, Netherlands
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* [[1985 IMO]] (in Finland)
 
* [[1985 IMO]] (in Finland)
* [[1985 IMO Problems]]
 
 
* [[1985 IMO Problems/Problem 1 | Problem 1]] proposed by Frank Budden, United Kingdom
 
* [[1985 IMO Problems/Problem 1 | Problem 1]] proposed by Frank Budden, United Kingdom
 
* [[1985 IMO Problems/Problem 2 | Problem 2]] proposed by George Szekeres, Australia
 
* [[1985 IMO Problems/Problem 2 | Problem 2]] proposed by George Szekeres, Australia
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* [[1986 IMO]] (in Poland)
 
* [[1986 IMO]] (in Poland)
* [[1986 IMO Problems]]
 
 
* [[1986 IMO Problems/Problem 1 | Problem 1]] proposed by Arthur Engel, West Germany
 
* [[1986 IMO Problems/Problem 1 | Problem 1]] proposed by Arthur Engel, West Germany
 
* [[1986 IMO Problems/Problem 2 | Problem 2]] proposed by Gengzhe Chang and Dongxu Qi, China
 
* [[1986 IMO Problems/Problem 2 | Problem 2]] proposed by Gengzhe Chang and Dongxu Qi, China
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* [[1987 IMO]] (in Cuba)
 
* [[1987 IMO]] (in Cuba)
* [[1987 IMO Problems]]
 
 
* [[1987 IMO Problems/Problem 1 | Problem 1]] proposed by Horst Sewerin, West Germany
 
* [[1987 IMO Problems/Problem 1 | Problem 1]] proposed by Horst Sewerin, West Germany
 
* [[1987 IMO Problems/Problem 2 | Problem 2]] proposed by I.A. Kushnir, USSR
 
* [[1987 IMO Problems/Problem 2 | Problem 2]] proposed by I.A. Kushnir, USSR
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* [[1988 IMO]] (in Australia)
 
* [[1988 IMO]] (in Australia)
* [[1988 IMO Problems]]
 
 
* [[1988 IMO Problems/Problem 1 | Problem 1]] proposed by Lucien Kieffer, Luxembourg
 
* [[1988 IMO Problems/Problem 1 | Problem 1]] proposed by Lucien Kieffer, Luxembourg
 
* [[1988 IMO Problems/Problem 2 | Problem 2]] proposed by Czechoslovakia
 
* [[1988 IMO Problems/Problem 2 | Problem 2]] proposed by Czechoslovakia
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* [[1989 IMO]] (in West Germany)
 
* [[1989 IMO]] (in West Germany)
* [[1989 IMO Problems]]
 
 
* [[1989 IMO Problems/Problem 1 | Problem 1]] proposed by Severino Gervacio and Jose Marasigan, Philippines
 
* [[1989 IMO Problems/Problem 1 | Problem 1]] proposed by Severino Gervacio and Jose Marasigan, Philippines
 
* [[1989 IMO Problems/Problem 2 | Problem 2]] proposed by Esther Szekeres, Australia
 
* [[1989 IMO Problems/Problem 2 | Problem 2]] proposed by Esther Szekeres, Australia
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* [[1990 IMO]] (in China)
 
* [[1990 IMO]] (in China)
* [[1990 IMO Problems]]
 
 
* [[1990 IMO Problems/Problem 1 | Problem 1]] proposed by C.R. Pranesachar, India
 
* [[1990 IMO Problems/Problem 1 | Problem 1]] proposed by C.R. Pranesachar, India
 
* [[1990 IMO Problems/Problem 2 | Problem 2]] proposed by Pavol Černek, Czechoslovakia
 
* [[1990 IMO Problems/Problem 2 | Problem 2]] proposed by Pavol Černek, Czechoslovakia
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* [[1991 IMO]] (in Sweden)
 
* [[1991 IMO]] (in Sweden)
* [[1991 IMO Problems]]
 
 
* [[1991 IMO Problems/Problem 1 | Problem 1]] proposed by Arkadii Skopenkov, USSR
 
* [[1991 IMO Problems/Problem 1 | Problem 1]] proposed by Arkadii Skopenkov, USSR
 
* [[1991 IMO Problems/Problem 2 | Problem 2]] proposed by Laurentiu Panaitopol, Romania
 
* [[1991 IMO Problems/Problem 2 | Problem 2]] proposed by Laurentiu Panaitopol, Romania
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* [[1992 IMO]] (in Russia)
 
* [[1992 IMO]] (in Russia)
* [[1992 IMO Problems]]
 
 
* [[1992 IMO Problems/Problem 1 | Problem 1]] proposed by Achim Zulauf, New Zealand
 
* [[1992 IMO Problems/Problem 1 | Problem 1]] proposed by Achim Zulauf, New Zealand
 
* [[1992 IMO Problems/Problem 2 | Problem 2]] proposed by Belur Jana Venkatachala, India
 
* [[1992 IMO Problems/Problem 2 | Problem 2]] proposed by Belur Jana Venkatachala, India
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* [[1993 IMO]] (in Turkey)
 
* [[1993 IMO]] (in Turkey)
* [[1993 IMO Problems]]
 
 
* [[1993 IMO Problems/Problem 1 | Problem 1]] proposed by Tom Laffey, Ireland
 
* [[1993 IMO Problems/Problem 1 | Problem 1]] proposed by Tom Laffey, Ireland
 
* [[1993 IMO Problems/Problem 2 | Problem 2]] proposed by David Monk, United Kingdom
 
* [[1993 IMO Problems/Problem 2 | Problem 2]] proposed by David Monk, United Kingdom
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* [[1994 IMO]] (in Hong Kong)
 
* [[1994 IMO]] (in Hong Kong)
* [[1994 IMO Problems]]
 
 
* [[1994 IMO Problems/Problem 1 | Problem 1]] proposed by Vincent Lafforgue, France
 
* [[1994 IMO Problems/Problem 1 | Problem 1]] proposed by Vincent Lafforgue, France
 
* [[1994 IMO Problems/Problem 2 | Problem 2]] proposed by Hans Lausch, Australia and Garnik Tonoyan, Armenia (independently)
 
* [[1994 IMO Problems/Problem 2 | Problem 2]] proposed by Hans Lausch, Australia and Garnik Tonoyan, Armenia (independently)
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* [[1995 IMO]] (in Canada)
 
* [[1995 IMO]] (in Canada)
* [[1995 IMO Problems]]
 
 
* [[1995 IMO Problems/Problem 1 | Problem 1]] proposed by Borislav Mihailov, Bulgaria
 
* [[1995 IMO Problems/Problem 1 | Problem 1]] proposed by Borislav Mihailov, Bulgaria
 
* [[1995 IMO Problems/Problem 2 | Problem 2]] proposed by Nazar Agakhanov, Russia
 
* [[1995 IMO Problems/Problem 2 | Problem 2]] proposed by Nazar Agakhanov, Russia
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* [[1996 IMO]] (in India)
 
* [[1996 IMO]] (in India)
* [[1996 IMO Problems]]
 
 
* [[1996 IMO Problems/Problem 1 | Problem 1]] proposed by Kerkko Luosto, Finland
 
* [[1996 IMO Problems/Problem 1 | Problem 1]] proposed by Kerkko Luosto, Finland
 
* [[1996 IMO Problems/Problem 2 | Problem 2]] proposed by Jeffrey Grossman, Canada
 
* [[1996 IMO Problems/Problem 2 | Problem 2]] proposed by Jeffrey Grossman, Canada
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* [[1997 IMO]] (in Argentina)
 
* [[1997 IMO]] (in Argentina)
* [[1997 IMO Problems]]
 
 
* [[1997 IMO Problems/Problem 1 | Problem 1]] proposed by Igor Akylich and Igor Voronovich, Belarus
 
* [[1997 IMO Problems/Problem 1 | Problem 1]] proposed by Igor Akylich and Igor Voronovich, Belarus
 
* [[1997 IMO Problems/Problem 2 | Problem 2]] proposed by David Monk, United Kingdom
 
* [[1997 IMO Problems/Problem 2 | Problem 2]] proposed by David Monk, United Kingdom
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* [[1998 IMO]] (in Taiwan)
 
* [[1998 IMO]] (in Taiwan)
* [[1998 IMO Problems]]
 
 
* [[1998 IMO Problems/Problem 1 | Problem 1]] proposed by Charles Leytem, Luxembourg
 
* [[1998 IMO Problems/Problem 1 | Problem 1]] proposed by Charles Leytem, Luxembourg
 
* [[1998 IMO Problems/Problem 2 | Problem 2]] proposed by Ravi B. Bapat, India
 
* [[1998 IMO Problems/Problem 2 | Problem 2]] proposed by Ravi B. Bapat, India
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* [[1999 IMO]] (in Romania)
 
* [[1999 IMO]] (in Romania)
* [[1999 IMO Problems]]
 
 
* [[1999 IMO Problems/Problem 1 | Problem 1]] proposed by Jan Willemson, Estonia
 
* [[1999 IMO Problems/Problem 1 | Problem 1]] proposed by Jan Willemson, Estonia
 
* [[1999 IMO Problems/Problem 2 | Problem 2]] proposed by Marcin Kuczma, Poland
 
* [[1999 IMO Problems/Problem 2 | Problem 2]] proposed by Marcin Kuczma, Poland
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* [[2000 IMO]] (in South-Korea)
 
* [[2000 IMO]] (in South-Korea)
* [[2000 IMO Problems]]
 
 
* [[2000 IMO Problems/Problem 1 | Problem 1]] proposed by Sergei Berlov, Russia
 
* [[2000 IMO Problems/Problem 1 | Problem 1]] proposed by Sergei Berlov, Russia
 
* [[2000 IMO Problems/Problem 2 | Problem 2]] proposed by Titu Andreescu, USA
 
* [[2000 IMO Problems/Problem 2 | Problem 2]] proposed by Titu Andreescu, USA
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* [[2001 IMO]] (in USA)
 
* [[2001 IMO]] (in USA)
* [[2001 IMO Problems]]
 
 
* [[2001 IMO Problems/Problem 1 | Problem 1]] proposed by Hojoo Lee, South Korea
 
* [[2001 IMO Problems/Problem 1 | Problem 1]] proposed by Hojoo Lee, South Korea
 
* [[2001 IMO Problems/Problem 2 | Problem 2]] proposed by Hojoo Lee, South Korea
 
* [[2001 IMO Problems/Problem 2 | Problem 2]] proposed by Hojoo Lee, South Korea
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* [[2002 IMO]] (in United Kingdom)
 
* [[2002 IMO]] (in United Kingdom)
* [[2002 IMO Problems]]
 
 
* [[2002 IMO Problems/Problem 1 | Problem 1]] proposed by Federico Ardila, Colombia
 
* [[2002 IMO Problems/Problem 1 | Problem 1]] proposed by Federico Ardila, Colombia
 
* [[2002 IMO Problems/Problem 2 | Problem 2]] proposed by Hojoo Lee, South Korea
 
* [[2002 IMO Problems/Problem 2 | Problem 2]] proposed by Hojoo Lee, South Korea
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* [[2003 IMO]] (in Japan)
 
* [[2003 IMO]] (in Japan)
* [[2003 IMO Problems]]
 
 
* [[2003 IMO Problems/Problem 1 | Problem 1]] proposed by Carlos Gustavo Moreira, Brazil
 
* [[2003 IMO Problems/Problem 1 | Problem 1]] proposed by Carlos Gustavo Moreira, Brazil
 
* [[2003 IMO Problems/Problem 2 | Problem 2]] proposed by Aleksander Ivanov, Bulgaria
 
* [[2003 IMO Problems/Problem 2 | Problem 2]] proposed by Aleksander Ivanov, Bulgaria
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* [[2004 IMO]] (in Greece)
 
* [[2004 IMO]] (in Greece)
* [[2004 IMO Problems]]
 
 
* [[2004 IMO Problems/Problem 1 | Problem 1]] proposed by  Dinu Serbanescu and Valentin Vornicu, Romania
 
* [[2004 IMO Problems/Problem 1 | Problem 1]] proposed by  Dinu Serbanescu and Valentin Vornicu, Romania
 
* [[2004 IMO Problems/Problem 2 | Problem 2]] proposed by Hojoo Lee, South Korea
 
* [[2004 IMO Problems/Problem 2 | Problem 2]] proposed by Hojoo Lee, South Korea
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* [[2005 IMO]] (in Mexico)
 
* [[2005 IMO]] (in Mexico)
* [[2005 IMO Problems]]
 
 
* [[2005 IMO Problems/Problem 1 | Problem 1]] proposed by Bogdan Enescu, Romania
 
* [[2005 IMO Problems/Problem 1 | Problem 1]] proposed by Bogdan Enescu, Romania
 
* [[2005 IMO Problems/Problem 2 | Problem 2]] proposed by Nicholas de Bruijn, Netherlands
 
* [[2005 IMO Problems/Problem 2 | Problem 2]] proposed by Nicholas de Bruijn, Netherlands
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* [[2006 IMO]] (in Slovenia)
 
* [[2006 IMO]] (in Slovenia)
* [[2006 IMO Problems]]
 
 
* [[2006 IMO Problems/Problem 1 | Problem 1]] proposed by Hojoo Lee, South Korea
 
* [[2006 IMO Problems/Problem 1 | Problem 1]] proposed by Hojoo Lee, South Korea
 
* [[2006 IMO Problems/Problem 2 | Problem 2]] proposed by Dušan Djukić, Serbia
 
* [[2006 IMO Problems/Problem 2 | Problem 2]] proposed by Dušan Djukić, Serbia
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* [[2007 IMO]] (in Vietnam)
 
* [[2007 IMO]] (in Vietnam)
* [[2007 IMO Problems]]
 
 
* [[2007 IMO Problems/Problem 1 | Problem 1]] proposed by Michael Albert, New Zealand
 
* [[2007 IMO Problems/Problem 1 | Problem 1]] proposed by Michael Albert, New Zealand
 
* [[2007 IMO Problems/Problem 2 | Problem 2]] proposed by Charles Leytem, Luxembourg
 
* [[2007 IMO Problems/Problem 2 | Problem 2]] proposed by Charles Leytem, Luxembourg
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* [[2008 IMO]] (in Spain)
 
* [[2008 IMO]] (in Spain)
* [[2008 IMO Problems]]
 
 
* [[2008 IMO Problems/Problem 1 | Problem 1]] proposed by Andrey Gavrilyuk, Russia  
 
* [[2008 IMO Problems/Problem 1 | Problem 1]] proposed by Andrey Gavrilyuk, Russia  
 
* [[2008 IMO Problems/Problem 2 | Problem 2]] proposed by Walther Janous, Austria  
 
* [[2008 IMO Problems/Problem 2 | Problem 2]] proposed by Walther Janous, Austria  
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* [[2009 IMO]] (in Germany)
 
* [[2009 IMO]] (in Germany)
* [[2009 IMO Problems]]
 
 
* [[2009 IMO Problems/Problem 1 | Problem 1]] proposed by Ross Atkins, Australia  
 
* [[2009 IMO Problems/Problem 1 | Problem 1]] proposed by Ross Atkins, Australia  
 
* [[2009 IMO Problems/Problem 2 | Problem 2]] proposed by Sergei Berlov, Russia  
 
* [[2009 IMO Problems/Problem 2 | Problem 2]] proposed by Sergei Berlov, Russia  
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* [[2010 IMO]] (in Kazakhstan)
 
* [[2010 IMO]] (in Kazakhstan)
* [[2010 IMO Problems]]
 
 
* [[2010 IMO Problems/Problem 1 | Problem 1]] proposed by Pierre Bornsztein, France  
 
* [[2010 IMO Problems/Problem 1 | Problem 1]] proposed by Pierre Bornsztein, France  
 
* [[2010 IMO Problems/Problem 2 | Problem 2]] proposed by Tai Wai Ming and Wang Chongli, Hong Kong  
 
* [[2010 IMO Problems/Problem 2 | Problem 2]] proposed by Tai Wai Ming and Wang Chongli, Hong Kong  
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* [[2011 IMO]] (in the Netherlands)
 
* [[2011 IMO]] (in the Netherlands)
* [[2011 IMO Problems]]
 
 
* [[2011 IMO Problems/Problem 1 | Problem 1]] proposed by Fernando Campos, Mexico
 
* [[2011 IMO Problems/Problem 1 | Problem 1]] proposed by Fernando Campos, Mexico
 
* [[2011 IMO Problems/Problem 2 | Problem 2]] proposed by Geoff Smith, United Kingdom
 
* [[2011 IMO Problems/Problem 2 | Problem 2]] proposed by Geoff Smith, United Kingdom
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* [[2011 IMO Problems/Problem 4 | Problem 4]] proposed by Morteza Saghafiyan, Iran
 
* [[2011 IMO Problems/Problem 4 | Problem 4]] proposed by Morteza Saghafiyan, Iran
 
* [[2011 IMO Problems/Problem 5 | Problem 5]] proposed by Seyedmahyar Sefidgaran, Iran
 
* [[2011 IMO Problems/Problem 5 | Problem 5]] proposed by Seyedmahyar Sefidgaran, Iran
* [[2011 IMO Problems/Problem 6 | Problem 6]] proposed by Japan
+
* [[2011 IMO Problems/Problem 6 | Problem 6]] proposed by Japanese PSC, Japan
  
 
== 2012 ==
 
== 2012 ==
  
 
* [[2012 IMO]] (in Argentina)
 
* [[2012 IMO]] (in Argentina)
* [[2012 IMO Problems]]
 
 
* [[2012 IMO Problems/Problem 1 | Problem 1]] proposed by Evangelos Psychas, Greece
 
* [[2012 IMO Problems/Problem 1 | Problem 1]] proposed by Evangelos Psychas, Greece
 
* [[2012 IMO Problems/Problem 2 | Problem 2]] proposed by Angelo di Pasquale, Australia
 
* [[2012 IMO Problems/Problem 2 | Problem 2]] proposed by Angelo di Pasquale, Australia
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* [[2012 IMO Problems/Problem 6 | Problem 6]] proposed by Dušan Djukić, Serbia
 
* [[2012 IMO Problems/Problem 6 | Problem 6]] proposed by Dušan Djukić, Serbia
  
 +
== 2013 ==
 +
 +
* [[2013 IMO]] (in Colombia)
 +
* [[2013 IMO Problems/Problem 1 | Problem 1]] proposed by Japanese PSC, Japan
 +
* [[2013 IMO Problems/Problem 2 | Problem 2]] proposed by Ivan Guo, Australia
 +
* [[2013 IMO Problems/Problem 3 | Problem 3]] proposed by Alexander A. Polyansky, Russia
 +
* [[2013 IMO Problems/Problem 4 | Problem 4]] proposed by Warut Suksompong and Potcharapol Suteparuk, Thailand
 +
* [[2013 IMO Problems/Problem 5 | Problem 5]] proposed by Nikolai Nikolov, Bulgaria
 +
* [[2013 IMO Problems/Problem 6 | Problem 6]] proposed by Alexander S. Golovanov and Mikhail A. Ivanov, Russia
 +
 +
== 2014 ==
 +
 +
* [[2014 IMO]] (in South Africa)
 +
* [[2014 IMO Problems/Problem 1 | Problem 1]] proposed by Gerhard Woeginger, Austria
 +
* [[2014 IMO Problems/Problem 2 | Problem 2]] proposed by Tonči Kokan, Croatia
 +
* [[2014 IMO Problems/Problem 3 | Problem 3]] proposed by Ali Zamani, Iran
 +
* [[2014 IMO Problems/Problem 4 | Problem 4]] proposed by Giorgi Arabidze, Georgia
 +
* [[2014 IMO Problems/Problem 5 | Problem 5]] proposed by Gerhard Woeginger, Luxembourg
 +
* [[2014 IMO Problems/Problem 6 | Problem 6]] proposed by Gerhard Woeginger, Austria
 +
 +
== 2015 ==
 +
 +
* [[2015 IMO]] (in Thailand)
 +
* [[2015 IMO Problems/Problem 1 | Problem 1]] proposed by Merlijn Staps, Netherlands
 +
* [[2015 IMO Problems/Problem 2 | Problem 2]] proposed by Dušan Djukić, Serbia
 +
* [[2015 IMO Problems/Problem 3 | Problem 3]] proposed by Danylo Khilko and Mykhailo Plotnikov, Ukraine
 +
* [[2015 IMO Problems/Problem 4 | Problem 4]] proposed by Silouanos Brazitikos and Evangelos Psychas, Greece
 +
* [[2015 IMO Problems/Problem 5 | Problem 5]] proposed by Dorlir Ahmeti, Albania
 +
* [[2015 IMO Problems/Problem 6 | Problem 6]] proposed by Ross Atkins and Ivan Guo, Australia
 +
 +
== 2016 ==
 +
 +
* [[2016 IMO]] (in Hong Kong)
 +
* [[2016 IMO Problems/Problem 1 | Problem 1]] proposed by Art Waeterschoot, Belgium
 +
* [[2016 IMO Problems/Problem 2 | Problem 2]] proposed by Trevor Tao, Australia
 +
* [[2016 IMO Problems/Problem 3 | Problem 3]] proposed by Aleksandr Gaifullin, Russia
 +
* [[2016 IMO Problems/Problem 4 | Problem 4]] proposed by Gerhard Woeginger, Luxembourg
 +
* [[2016 IMO Problems/Problem 5 | Problem 5]] proposed by Nazar Agakhanov and Ilya Bogdanov, Russia
 +
* [[2016 IMO Problems/Problem 6 | Problem 6]] proposed by Josef Tkadlec, Czech Republic
 +
 +
== 2017 ==
 +
 +
* [[2017 IMO]] (in Brazil)
 +
* [[2017 IMO Problems/Problem 1 | Problem 1]] proposed by Stephan Wagner, South Africa
 +
* [[2017 IMO Problems/Problem 2 | Problem 2]] proposed by Dorlir Ahmeti, Albania
 +
* [[2017 IMO Problems/Problem 3 | Problem 3]] proposed by Gerhard Woeginger, Austria
 +
* [[2017 IMO Problems/Problem 4 | Problem 4]] proposed by Charles Leytem, Luxembourg
 +
* [[2017 IMO Problems/Problem 5 | Problem 5]] proposed by Grigory Chelnokov, Russia
 +
* [[2017 IMO Problems/Problem 6 | Problem 6]] proposed by John Berman, USA
 +
 +
== 2018 ==
 +
 +
* [[2018 IMO]] (in Romania)
 +
* [[2018 IMO Problems/Problem 1 | Problem 1]] proposed by Silouanos Brazitikos, Evangelos Psychas and Michael Sarantis, Greece
 +
* [[2018 IMO Problems/Problem 2 | Problem 2]] proposed by Patrik Bak, Slovakia
 +
* [[2018 IMO Problems/Problem 3 | Problem 3]] proposed by Morteza Saghafian, Iran
 +
* [[2018 IMO Problems/Problem 4 | Problem 4]] proposed by Gurgen Asatryan, Armenia
 +
* [[2018 IMO Problems/Problem 5 | Problem 5]] proposed by Bayarmagnai Gombodorj, Mongolia
 +
* [[2018 IMO Problems/Problem 6 | Problem 6]] proposed by Tomasz Ciesla, Poland
 +
 +
== 2019 ==
 +
 +
* [[2019 IMO]] (in England)
 +
* [[2019 IMO Problems/Problem 1 | Problem 1]] proposed by Liam Baker, South Africa
 +
* [[2019 IMO Problems/Problem 2 | Problem 2]] proposed by Anton Trygub, Ukraine
 +
* [[2019 IMO Problems/Problem 3 | Problem 3]] proposed by Adrian Beker, Croatia
 +
* [[2019 IMO Problems/Problem 4 | Problem 4]] proposed by Gabriel Chicas Reyes, El Salvador
 +
* [[2019 IMO Problems/Problem 5 | Problem 5]] proposed by David Altizio, USA
 +
* [[2019 IMO Problems/Problem 6 | Problem 6]] proposed by Anant Mudgal, India
  
 
== Comment ==
 
== Comment ==
Line 602: Line 618:
 
== See also ==
 
== See also ==
  
* [[IMO problems statistics]]
+
* [[IMO problems statistics]] (eternal)
 +
* [[IMO problems statistics since 2000]] (modern history)
 
* [http://www.artofproblemsolving.com/Forum/resources.php?c=1&cid=16 IMO problems on the Resources page]
 
* [http://www.artofproblemsolving.com/Forum/resources.php?c=1&cid=16 IMO problems on the Resources page]
 
* [[IMO Shortlist Problems]]
 
* [[IMO Shortlist Problems]]

Revision as of 13:08, 18 July 2019

This page lists the authors and the proposing countries of the problems of the IMO.

1959

1960

1961

1962

1963

1964

1965

1966

1967

1968

1969

1970

1971

1972

1973

1974

1975

1976

1977

1978

1979

  • 1979 IMO (in United Kingdom)
  • Problem 1 proposed by Arthur Engel, West Germany
  • Problem 2 proposed by Nickolay Khadzhiivanov and Nedjalko Nenov, Bulgaria
  • Problem 3 proposed by Nikolai Vasil'ev and Igor F. Sharygin, USSR
  • Problem 4 proposed by Murray Klamkin, USA
  • Problem 5 proposed by Joe Gillis, Israel
  • Problem 6 proposed by Arthur Engel, West Germany

1980

There was no IMO in 1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

  • 1994 IMO (in Hong Kong)
  • Problem 1 proposed by Vincent Lafforgue, France
  • Problem 2 proposed by Hans Lausch, Australia and Garnik Tonoyan, Armenia (independently)
  • Problem 3 proposed by Gabriel Istrate, Romania
  • Problem 4 proposed by Hans Lausch, Australia
  • Problem 5 proposed by David Monk, United Kingdom
  • Problem 6 proposed by Kerkko Luosto, Finland

1995

1996

1997

  • 1997 IMO (in Argentina)
  • Problem 1 proposed by Igor Akylich and Igor Voronovich, Belarus
  • Problem 2 proposed by David Monk, United Kingdom
  • Problem 3 proposed by Oleg Bogopolsky, Russia
  • Problem 4 proposed by Ebadollah S. Mahmoodian and Mohammad Mahdian, Iran
  • Problem 5 proposed by Petr Kanovsky, Czech Republic
  • Problem 6 proposed by Giedrius Alkauskas, Lithuania

1998

1999

2000

2001

  • 2001 IMO (in USA)
  • Problem 1 proposed by Hojoo Lee, South Korea
  • Problem 2 proposed by Hojoo Lee, South Korea
  • Problem 3 proposed by Christian Bey, Germany
  • Problem 4 proposed by Bill Sands, Canada
  • Problem 5 proposed by Shay Gueron, Israel. (Also: Problem 2501 in Crux Mathematicorum, February 2000)
  • Problem 6 proposed by Aleksander Ivanov, Bulgaria

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

  • 2013 IMO (in Colombia)
  • Problem 1 proposed by Japanese PSC, Japan
  • Problem 2 proposed by Ivan Guo, Australia
  • Problem 3 proposed by Alexander A. Polyansky, Russia
  • Problem 4 proposed by Warut Suksompong and Potcharapol Suteparuk, Thailand
  • Problem 5 proposed by Nikolai Nikolov, Bulgaria
  • Problem 6 proposed by Alexander S. Golovanov and Mikhail A. Ivanov, Russia

2014

2015

  • 2015 IMO (in Thailand)
  • Problem 1 proposed by Merlijn Staps, Netherlands
  • Problem 2 proposed by Dušan Djukić, Serbia
  • Problem 3 proposed by Danylo Khilko and Mykhailo Plotnikov, Ukraine
  • Problem 4 proposed by Silouanos Brazitikos and Evangelos Psychas, Greece
  • Problem 5 proposed by Dorlir Ahmeti, Albania
  • Problem 6 proposed by Ross Atkins and Ivan Guo, Australia

2016

2017

2018

  • 2018 IMO (in Romania)
  • Problem 1 proposed by Silouanos Brazitikos, Evangelos Psychas and Michael Sarantis, Greece
  • Problem 2 proposed by Patrik Bak, Slovakia
  • Problem 3 proposed by Morteza Saghafian, Iran
  • Problem 4 proposed by Gurgen Asatryan, Armenia
  • Problem 5 proposed by Bayarmagnai Gombodorj, Mongolia
  • Problem 6 proposed by Tomasz Ciesla, Poland

2019

Comment

This page lists the authors and the proposing countries of the problems of the IMO.

For many problems, the composers do not have the nationality of the proposing country. For instance, problem 2009/4 was proposed by Belgium, but only two of the three problem authors were Belgian, whereas the third is from South-Korea.

To the current moment, there is only a single IMO problem that has two distinct proposing countries: The if-part of problem 1994/2 was proposed by Australia and its only-if part by Armenia.

See also