User contributions
(newest | oldest) View (newer 100 | older 100) (20 | 50 | 100 | 250 | 500)
- 15:33, 5 May 2011 (diff | hist) . . (+33) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 15:32, 5 May 2011 (diff | hist) . . (+11) . . 2011 USAMO Problems/Problem 6 (→Existence)
- 15:31, 5 May 2011 (diff | hist) . . (+11) . . 2011 USAMO Problems/Problem 6 (→Existence)
- 15:31, 5 May 2011 (diff | hist) . . (+12) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 15:29, 5 May 2011 (diff | hist) . . (-2) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 15:28, 5 May 2011 (diff | hist) . . (-4) . . 2011 USAMO Problems/Problem 6 (→Solution)
- 18:46, 3 May 2011 (diff | hist) . . (+3,797) . . N 2011 USAMO Problems/Problem 6 (Created page with '==Problem== Let <math>A</math> be a set with <math>|A| = 225</math>, meaning that <math>A</math> has 225 elements. Suppose further that there are eleven subsets <math>A_1</math>…')
- 11:42, 29 April 2011 (diff | hist) . . (+35) . . m 2011 USAMO Problems/Problem 2 (→See also)
- 11:42, 29 April 2011 (diff | hist) . . (+35) . . m 2011 USAMO Problems/Problem 4 (→See also)
- 11:38, 29 April 2011 (diff | hist) . . (+57) . . 2011 USAMO Problems/Problem 4 (Added footer)
- 11:37, 29 April 2011 (diff | hist) . . (+57) . . m 2011 USAMO Problems/Problem 2 (Added footer)
- 11:36, 29 April 2011 (diff | hist) . . (+82) . . m 2011 USAMO Problems/Problem 1 (Added footer)
- 11:29, 29 April 2011 (diff | hist) . . (+1,487) . . N 2011 USAMO Problems/Problem 4 (Since 2^n is 1 mod (2^n-1), reduce the exponent mod n, we can't win with n prime, but n=p^2 will do...)
- 11:22, 29 April 2011 (diff | hist) . . (+3,379) . . 2011 USAMO Problems/Problem 2 (Zeroing adjacent vertices and looking at how the opposites become winnable solves the problem)
- 11:11, 29 April 2011 (diff | hist) . . (-4) . . m 2011 USAMO Problems (Corrected typo.)
- 11:09, 29 April 2011 (diff | hist) . . (+694) . . N 2011 USAMO Problems/Problem 2 (Created page with '==Problem== An integer is assigned to each vertex of a regular pentagon so that the sum of the five integers is 2011. A turn of a solitaire game consists of subtracting an intege…')
- 11:06, 29 April 2011 (diff | hist) . . (+1,978) . . N 2011 USAMO Problems/Problem 1 (Solution by change of variables and AM-GM)
- 01:05, 3 April 2011 (diff | hist) . . (+481) . . 2011 AIME II Problems/Problem 2
- 15:42, 2 April 2011 (diff | hist) . . (+4) . . 2011 AIME II Problems/Problem 9 (→Solution)
- 02:00, 2 April 2011 (diff | hist) . . (+1,230) . . 2011 AIME II Problems/Problem 12
- 01:30, 2 April 2011 (diff | hist) . . (-7) . . 2011 AIME II Problems/Problem 3
- 01:20, 2 April 2011 (diff | hist) . . (+140) . . 2011 AIME II Problems/Problem 1
- 01:08, 2 April 2011 (diff | hist) . . (+29) . . 2011 AIME II Problems/Problem 6 (→Solution)
- 01:05, 2 April 2011 (diff | hist) . . (-776) . . 2011 AIME II Problems/Problem 6
- 00:41, 2 April 2011 (diff | hist) . . (-4) . . 2011 AIME II Problems/Problem 9 (→Solution)
- 00:38, 2 April 2011 (diff | hist) . . (+529) . . 2011 AIME II Problems/Problem 9 (→Solution)
- 23:42, 1 April 2011 (diff | hist) . . (+948) . . 2011 AIME II Problems/Problem 9
- 17:47, 1 April 2011 (diff | hist) . . (0) . . 2011 AIME II Problems/Problem 9
- 17:46, 1 April 2011 (diff | hist) . . (+14) . . 2011 AIME II Problems (→Problem 9)
- 17:45, 1 April 2011 (diff | hist) . . (+53) . . 2011 AIME II Problems/Problem 9
- 17:03, 26 March 2011 (diff | hist) . . (+69) . . 1983 AIME Problems/Problem 11 (→Solution 1)
- 16:59, 26 March 2011 (diff | hist) . . (+33) . . 1983 AIME Problems/Problem 11 (→Problem)
- 16:44, 26 March 2011 (diff | hist) . . (+27) . . 1983 AIME Problems (Asy now compiles and gives sensible output)
- 15:18, 14 May 2010 (diff | hist) . . (+6) . . USAJMO Problems and Solutions
- 01:18, 14 May 2010 (diff | hist) . . (0) . . 2005 AIME II Problems/Problem 15 (→Problem)
- 19:48, 12 May 2010 (diff | hist) . . (+85) . . 2010 USAMO Problems/Problem 4 (TeX cleanup)
- 19:42, 12 May 2010 (diff | hist) . . (+2) . . 2010 USAMO Problems/Problem 4 (→Solution)
- 19:37, 12 May 2010 (diff | hist) . . (+4,571) . . 2010 USAMO Problems/Problem 4 (→Solution)
- 10:12, 12 May 2010 (diff | hist) . . (+6) . . 2010 USAJMO
- 10:10, 12 May 2010 (diff | hist) . . (+36) . . United States of America Mathematical Olympiad (Add USAJMO link)
- 10:07, 12 May 2010 (diff | hist) . . (-2) . . 2010 USAJMO
- 10:05, 12 May 2010 (diff | hist) . . (+36) . . AMC Problems and Solutions (Add USAJMO link)
- 23:59, 11 May 2010 (diff | hist) . . (+43) . . 2010 USAMO Problems (→Problem 5)
- 23:58, 11 May 2010 (diff | hist) . . (+41) . . 2010 USAMO Problems/Problem 5 (→Alternative Calculation)
- 15:51, 11 May 2010 (diff | hist) . . (+12) . . 2010 USAMO Problems/Problem 5 (→Solution)
- 15:33, 11 May 2010 (diff | hist) . . (+2,905) . . N 2010 USAMO Problems/Problem 5 (Created page with '==Problem== Let <math>q = \dfrac{3p-5}{2}</math> where <math>p</math> is an odd prime, and let <center> <cmath> S_q = \frac{1}{2\cdot 3 \cdot 4} + \frac{1}{5\cdot 6 \cdot 7}…')
- 12:01, 11 May 2010 (diff | hist) . . (+210) . . 2010 USAMO Problems/Problem 2 (→Solution)
- 11:33, 11 May 2010 (diff | hist) . . (+2,086) . . N 2010 USAMO Problems/Problem 2 (Created page with '==Problem== There are <math>n</math> students is standing in a circle, one behind the other. The students have heights <math>h_1 < h_2 < \ldots < h_n</math>. If a student with he…')
- 14:22, 9 May 2010 (diff | hist) . . (-413) . . 2010 USAMO Problems/Problem 1 (Cleaner asy code...)
- 01:29, 8 May 2010 (diff | hist) . . (+174) . . 2010 USAMO Problems/Problem 1 (→Solution)
- 16:34, 7 May 2010 (diff | hist) . . (0) . . 2010 USAMO Problems/Problem 3 (→Additional observations)
- 05:04, 7 May 2010 (diff | hist) . . (+5,844) . . N 2010 USAMO Problems/Problem 1 (Created page with '==Problem== Let <math>AXYZB</math> be a convex pentagon inscribed in a semicircle of diameter <math>AB</math>. Denote by <math>P, Q, R, S</math> the feet of the perpendiculars fr…')
- 01:24, 7 May 2010 (diff | hist) . . (-2) . . 2010 USAJMO Problems (→Problem 6)
- 00:54, 7 May 2010 (diff | hist) . . (+2,243) . . N 2010 USAJMO Problems/Problem 4 (Created page with '==Problem== A triangle is called a parabolic triangle if its vertices lie on a parabola <math>y = x^2</math>. Prove that for every nonnegative integer <math>n</math>, there is an…')
- 00:47, 7 May 2010 (diff | hist) . . (+2,495) . . N 2010 USAJMO Problems/Problem 5 (Created page with '==Problem== Two permutations <math>a_1, a_2, \ldots, a_{2010}</math> and <math>b_1, b_2, \ldots, b_{2010}</math> of the numbers <math>1, 2, \ldots, 2010</math> are said to inters…')
- 00:40, 7 May 2010 (diff | hist) . . (+2,955) . . N 2010 USAJMO Problems/Problem 2 (Created page with '==Problem== Let <math>n > 1</math> be an integer. Find, with proof, all sequences <math>x_1, x_2, \ldots, x_{n-1}</math> of positive integers with the following three properties:…')
- 00:34, 7 May 2010 (diff | hist) . . (+8) . . 2010 USAJMO Problems/Problem 1 (→Proof)
- 00:32, 7 May 2010 (diff | hist) . . (+3,040) . . N 2010 USAJMO Problems/Problem 1 (Created page with '==Problem== A permutation of the set of positive integers <math>[n] = {1,2,\ldots,n}</math> is a sequence <math>(a_1,a_2,\ldots,a_n)</math> such that each element of <math>[n]</m…')
- 00:19, 7 May 2010 (diff | hist) . . (+3,183) . . N 2010 USAJMO Problems (Created page with '=Day 1= ==Problem 1== A permutation of the set of positive integers <math>[n] = {1,2,\ldots,n}</math> is a sequence <math>(a_1,a_2,\ldots,a_n)</math> such that each element of <m…')
- 23:30, 6 May 2010 (diff | hist) . . (-3) . . 2010 USAJMO (→Resource)
- 12:58, 6 May 2010 (diff | hist) . . (+4) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 12:57, 6 May 2010 (diff | hist) . . (-96) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 12:53, 6 May 2010 (diff | hist) . . (-8) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 12:48, 6 May 2010 (diff | hist) . . (-2) . . 2010 USAMO Problems/Problem 4 (→Problem)
- 12:47, 6 May 2010 (diff | hist) . . (+473) . . 2010 USAMO Problems/Problem 4 (→Solution)
- 04:23, 6 May 2010 (diff | hist) . . (+365) . . 2010 USAMO Problems/Problem 3 (Minor tweaks and summary)
- 03:46, 6 May 2010 (diff | hist) . . (+890) . . 2010 USAMO Problems/Problem 3 (Derived formula for leading term of limit sequence)
- 19:01, 5 May 2010 (diff | hist) . . (+4,913) . . 2010 USAMO Problems/Problem 3 (Additional notes on the limit sequence)
- 17:19, 5 May 2010 (diff | hist) . . (-129) . . 2010 USAMO Problems/Problem 3 (Redundant)
- 17:12, 5 May 2010 (diff | hist) . . (+795) . . 2010 USAMO Problems/Problem 3 (Final copy after proof-reading...)
- 16:06, 5 May 2010 (diff | hist) . . (0) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 16:01, 5 May 2010 (diff | hist) . . (+153) . . 2010 USAMO Problems/Problem 3 (Work-around lack of automatic centering of displayed equations...)
- 00:09, 5 May 2010 (diff | hist) . . (+4,509) . . 2010 USAMO Problems/Problem 3 (Problem and solution. Displayed equations still look sub-optimal (not centered) and don't work right without a paragraph break... :-()
- 23:17, 4 May 2010 (diff | hist) . . (+287) . . N 2010 USAMO Problems/Problem 3 (Created page with '==Problem== The <math>2010</math> positive numbers <math>a_1, a_2, \ldots , a_{2010}</math> satisfy the inequality <math>a_ia_j \le i+j</math> for all distinct indices <math>i, j…')
- 00:00, 1 May 2010 (diff | hist) . . (+8) . . List of United States high school mathematics competitions (→National high school mathematics competitions)
- 17:28, 27 March 2010 (diff | hist) . . (-40) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 11:18, 26 March 2010 (diff | hist) . . (+236) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 01:10, 26 March 2010 (diff | hist) . . (-20) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 00:52, 26 March 2010 (diff | hist) . . (+4) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 00:50, 26 March 2010 (diff | hist) . . (+5) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 00:48, 26 March 2010 (diff | hist) . . (-3) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 00:46, 26 March 2010 (diff | hist) . . (+3,635) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 19:52, 21 March 2010 (diff | hist) . . (+1) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:47, 21 March 2010 (diff | hist) . . (+2) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:33, 21 March 2010 (diff | hist) . . (+5) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:31, 21 March 2010 (diff | hist) . . (+6) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:27, 21 March 2010 (diff | hist) . . (+115) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:21, 21 March 2010 (diff | hist) . . (+8) . . 2010 AIME I Problems/Problem 14 (Explicit solution with no guess-work.)
- 19:19, 21 March 2010 (diff | hist) . . (+8) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:16, 21 March 2010 (diff | hist) . . (+111) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:13, 21 March 2010 (diff | hist) . . (0) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:12, 21 March 2010 (diff | hist) . . (+1) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:11, 21 March 2010 (diff | hist) . . (+75) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:08, 21 March 2010 (diff | hist) . . (+1,165) . . 2010 AIME I Problems/Problem 14 (→See also)
- 14:55, 28 February 2010 (diff | hist) . . (+11) . . 2009 AIME I Problems/Problem 12 (→Solution 3)
- 14:53, 28 February 2010 (diff | hist) . . (+4) . . 2009 AIME I Problems/Problem 9
- 18:27, 27 February 2010 (diff | hist) . . (0) . . 2009 AIME I Problems/Problem 12 (→Solution 2)
- 18:22, 27 February 2010 (diff | hist) . . (0) . . 2009 AIME I Problems/Problem 12 (→Solution 3)
- 18:17, 27 February 2010 (diff | hist) . . (+1,724) . . 2009 AIME I Problems/Problem 12 (More elegant solution that shows the answer to be independent of the lengths of the sides of triangle)
- 17:31, 27 February 2010 (diff | hist) . . (0) . . 2009 AIME I Problems/Problem 5 (→Solution)
(newest | oldest) View (newer 100 | older 100) (20 | 50 | 100 | 250 | 500)