Difference between revisions of "2011 UNCO Math Contest II Problems/Problem 6"
(Created page with "== Problem == What is the remainder when <math>1! + 2! + 3! + ?+ 2011!</math> is divided by <math>18</math>? == Solution == == See Also == {{UNCO Math Contest box|n=II|year=...") |
(→Problem) |
||
(One intermediate revision by the same user not shown) | |||
Line 1: | Line 1: | ||
== Problem == | == Problem == | ||
− | What is the remainder when <math>1! + 2! + 3! + | + | What is the remainder when <math>1! + 2! + 3! + \cdots + 2011!</math> is divided by <math>18</math>? |
− | |||
== Solution == | == Solution == | ||
− | + | Since all the terms past <math>5!</math> are divisible by <math>18</math>, it is only necessary to look at the remainder resulted from the first 5 terms. | |
+ | <math>1!+2!+3!+4!+5!=153\equiv 9\pmod{18}</math> | ||
== See Also == | == See Also == |
Latest revision as of 23:42, 27 October 2015
Problem
What is the remainder when is divided by ?
Solution
Since all the terms past are divisible by , it is only necessary to look at the remainder resulted from the first 5 terms.
See Also
2011 UNCO Math Contest II (Problems • Answer Key • Resources) | ||
Preceded by Problem 5 |
Followed by Problem 7 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 | ||
All UNCO Math Contest Problems and Solutions |