# User contributions

- 01:40, 3 November 2011 (diff | hist) . . (-95) . . 1991 AIME Problems/Problem 11 (→Solution)
- 01:40, 3 November 2011 (diff | hist) . . (+6) . . 1991 AIME Problems/Problem 11 (→Problem)
- 01:38, 3 November 2011 (diff | hist) . . (0) . . File:AIME 1991 Problem 11.png (uploaded a new version of "File:AIME 1991 Problem 11.png": Better diagram) (current)
- 01:23, 3 November 2011 (diff | hist) . . (0) . . File:AIME 1991 Problem 11.png (uploaded a new version of "File:AIME 1991 Problem 11.png": Better diagram)
- 01:19, 3 November 2011 (diff | hist) . . (+14) . . N File:AIME 1991 Problem 11.png (Better diagram)
- 23:40, 10 May 2011 (diff | hist) . . (+44) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 23:32, 10 May 2011 (diff | hist) . . (-434) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 19:33, 9 May 2011 (diff | hist) . . (+25) . . 1988 IMO Problems/Problem 1 (→Problem)
- 19:27, 9 May 2011 (diff | hist) . . (+83) . . 1988 IMO Problems/Problem 1 (→Solution)
- 19:00, 9 May 2011 (diff | hist) . . (+11) . . 1988 IMO Problems/Problem 1
- 11:47, 6 May 2011 (diff | hist) . . (+163) . . 2011 USAMO Problems/Problem 4 (→Solution)
- 14:33, 5 May 2011 (diff | hist) . . (+11) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 14:33, 5 May 2011 (diff | hist) . . (+33) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 14:32, 5 May 2011 (diff | hist) . . (+11) . . 2011 USAMO Problems/Problem 6 (→Existence)
- 14:31, 5 May 2011 (diff | hist) . . (+11) . . 2011 USAMO Problems/Problem 6 (→Existence)
- 14:31, 5 May 2011 (diff | hist) . . (+12) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 14:29, 5 May 2011 (diff | hist) . . (-2) . . 2011 USAMO Problems/Problem 6 (→Minimality)
- 14:28, 5 May 2011 (diff | hist) . . (-4) . . 2011 USAMO Problems/Problem 6 (→Solution)
- 17:46, 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>…') - 10:42, 29 April 2011 (diff | hist) . . (+35) . . m 2011 USAMO Problems/Problem 2 (→See also)
- 10:42, 29 April 2011 (diff | hist) . . (+35) . . m 2011 USAMO Problems/Problem 4 (→See also)
- 10:38, 29 April 2011 (diff | hist) . . (+57) . . 2011 USAMO Problems/Problem 4 (Added footer)
- 10:37, 29 April 2011 (diff | hist) . . (+57) . . m 2011 USAMO Problems/Problem 2 (Added footer)
- 10:36, 29 April 2011 (diff | hist) . . (+82) . . m 2011 USAMO Problems/Problem 1 (Added footer)
- 10:29, 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...) - 10:22, 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) - 10:11, 29 April 2011 (diff | hist) . . (-4) . . m 2011 USAMO Problems (Corrected typo.)
- 10:09, 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…') - 10:06, 29 April 2011
(diff | hist) . .
**(+1,978)** . . N 2011 USAMO Problems/Problem 1 (Solution by change of variables and AM-GM) - 00:05, 3 April 2011 (diff | hist) . . (+481) . . 2011 AIME II Problems/Problem 2
- 14:42, 2 April 2011 (diff | hist) . . (+4) . . 2011 AIME II Problems/Problem 9 (→Solution)
- 01:00, 2 April 2011
(diff | hist) . .
**(+1,230)** . . 2011 AIME II Problems/Problem 12 - 00:30, 2 April 2011 (diff | hist) . . (-7) . . 2011 AIME II Problems/Problem 3
- 00:20, 2 April 2011 (diff | hist) . . (+140) . . 2011 AIME II Problems/Problem 1
- 00:08, 2 April 2011 (diff | hist) . . (+29) . . 2011 AIME II Problems/Problem 6 (→Solution)
- 00:05, 2 April 2011
(diff | hist) . .
**(-776)** . . 2011 AIME II Problems/Problem 6 - 23:41, 1 April 2011 (diff | hist) . . (-4) . . 2011 AIME II Problems/Problem 9 (→Solution)
- 23:38, 1 April 2011
(diff | hist) . .
**(+529)** . . 2011 AIME II Problems/Problem 9 (→Solution) - 22:42, 1 April 2011
(diff | hist) . .
**(+948)** . . 2011 AIME II Problems/Problem 9 - 16:47, 1 April 2011 (diff | hist) . . (0) . . 2011 AIME II Problems/Problem 9
- 16:46, 1 April 2011 (diff | hist) . . (+14) . . 2011 AIME II Problems (→Problem 9)
- 16:45, 1 April 2011 (diff | hist) . . (+53) . . 2011 AIME II Problems/Problem 9
- 16:03, 26 March 2011 (diff | hist) . . (+69) . . 1983 AIME Problems/Problem 11 (→Solution 1)
- 15:59, 26 March 2011 (diff | hist) . . (+33) . . 1983 AIME Problems/Problem 11 (→Problem)
- 15:44, 26 March 2011 (diff | hist) . . (+27) . . 1983 AIME Problems (Asy now compiles and gives sensible output)
- 14:18, 14 May 2010 (diff | hist) . . (+6) . . USAJMO Problems and Solutions
- 00:18, 14 May 2010 (diff | hist) . . (0) . . 2005 AIME II Problems/Problem 15 (→Problem)
- 18:48, 12 May 2010 (diff | hist) . . (+85) . . 2010 USAMO Problems/Problem 4 (TeX cleanup)
- 18:42, 12 May 2010 (diff | hist) . . (+2) . . 2010 USAMO Problems/Problem 4 (→Solution)
- 18:37, 12 May 2010
(diff | hist) . .
**(+4,571)** . . 2010 USAMO Problems/Problem 4 (→Solution) - 09:12, 12 May 2010 (diff | hist) . . (+6) . . 2010 USAJMO
- 09:10, 12 May 2010 (diff | hist) . . (+36) . . United States of America Mathematical Olympiad (Add USAJMO link)
- 09:07, 12 May 2010 (diff | hist) . . (-2) . . 2010 USAJMO
- 09:05, 12 May 2010 (diff | hist) . . (+36) . . AMC Problems and Solutions (Add USAJMO link)
- 22:59, 11 May 2010 (diff | hist) . . (+43) . . 2010 USAMO Problems (→Problem 5)
- 22:58, 11 May 2010 (diff | hist) . . (+41) . . 2010 USAMO Problems/Problem 5 (→Alternative Calculation)
- 14:51, 11 May 2010 (diff | hist) . . (+12) . . 2010 USAMO Problems/Problem 5 (→Solution)
- 14:33, 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}…') - 11:01, 11 May 2010 (diff | hist) . . (+210) . . 2010 USAMO Problems/Problem 2 (→Solution)
- 10:33, 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…') - 13:22, 9 May 2010 (diff | hist) . . (-413) . . 2010 USAMO Problems/Problem 1 (Cleaner asy code...)
- 00:29, 8 May 2010 (diff | hist) . . (+174) . . 2010 USAMO Problems/Problem 1 (→Solution)
- 15:34, 7 May 2010 (diff | hist) . . (0) . . 2010 USAMO Problems/Problem 3 (→Additional observations)
- 04:04, 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…') - 00:24, 7 May 2010 (diff | hist) . . (-2) . . 2010 USAJMO Problems (→Problem 6)
- 23:54, 6 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…') - 23:47, 6 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…') - 23:40, 6 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:…') - 23:34, 6 May 2010 (diff | hist) . . (+8) . . 2010 USAJMO Problems/Problem 1 (→Proof)
- 23:32, 6 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…') - 23:19, 6 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…') - 22:30, 6 May 2010 (diff | hist) . . (-3) . . 2010 USAJMO (→Resource)
- 11:58, 6 May 2010 (diff | hist) . . (+4) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 11:57, 6 May 2010 (diff | hist) . . (-96) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 11:53, 6 May 2010 (diff | hist) . . (-8) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 11:48, 6 May 2010 (diff | hist) . . (-2) . . 2010 USAMO Problems/Problem 4 (→Problem)
- 11:47, 6 May 2010 (diff | hist) . . (+473) . . 2010 USAMO Problems/Problem 4 (→Solution)
- 03:23, 6 May 2010 (diff | hist) . . (+365) . . 2010 USAMO Problems/Problem 3 (Minor tweaks and summary)
- 02:46, 6 May 2010
(diff | hist) . .
**(+890)** . . 2010 USAMO Problems/Problem 3 (Derived formula for leading term of limit sequence) - 18:01, 5 May 2010
(diff | hist) . .
**(+4,913)** . . 2010 USAMO Problems/Problem 3 (Additional notes on the limit sequence) - 16:19, 5 May 2010 (diff | hist) . . (-129) . . 2010 USAMO Problems/Problem 3 (Redundant)
- 16:12, 5 May 2010
(diff | hist) . .
**(+795)** . . 2010 USAMO Problems/Problem 3 (Final copy after proof-reading...) - 15:06, 5 May 2010 (diff | hist) . . (0) . . 2010 USAMO Problems/Problem 3 (→Proof)
- 15:01, 5 May 2010 (diff | hist) . . (+153) . . 2010 USAMO Problems/Problem 3 (Work-around lack of automatic centering of displayed equations...)
- 23:09, 4 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... :-() - 22:17, 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…')
- 23:00, 30 April 2010 (diff | hist) . . (+8) . . List of United States high school mathematics competitions (→National high school mathematics competitions)
- 16:28, 27 March 2010 (diff | hist) . . (-40) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 10:18, 26 March 2010 (diff | hist) . . (+236) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 00:10, 26 March 2010 (diff | hist) . . (-20) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 23:52, 25 March 2010 (diff | hist) . . (+4) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 23:50, 25 March 2010 (diff | hist) . . (+5) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 23:48, 25 March 2010 (diff | hist) . . (-3) . . 2006 USAMO Problems/Problem 3 (→Solution)
- 23:46, 25 March 2010
(diff | hist) . .
**(+3,635)** . . 2006 USAMO Problems/Problem 3 (→Solution) - 18:52, 21 March 2010 (diff | hist) . . (+1) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:47, 21 March 2010 (diff | hist) . . (+2) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:33, 21 March 2010 (diff | hist) . . (+5) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:31, 21 March 2010 (diff | hist) . . (+6) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:27, 21 March 2010 (diff | hist) . . (+115) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:21, 21 March 2010 (diff | hist) . . (+8) . . 2010 AIME I Problems/Problem 14 (Explicit solution with no guess-work.)
- 18:19, 21 March 2010 (diff | hist) . . (+8) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:16, 21 March 2010 (diff | hist) . . (+111) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:13, 21 March 2010 (diff | hist) . . (0) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:12, 21 March 2010 (diff | hist) . . (+1) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:11, 21 March 2010 (diff | hist) . . (+75) . . 2010 AIME I Problems/Problem 14 (→Solution 3)
- 18:08, 21 March 2010
(diff | hist) . .
**(+1,165)** . . 2010 AIME I Problems/Problem 14 (→See also) - 13:55, 28 February 2010 (diff | hist) . . (+11) . . 2009 AIME I Problems/Problem 12 (→Solution 3)
- 13:53, 28 February 2010 (diff | hist) . . (+4) . . 2009 AIME I Problems/Problem 9
- 17:27, 27 February 2010 (diff | hist) . . (0) . . 2009 AIME I Problems/Problem 12 (→Solution 2)
- 17:22, 27 February 2010 (diff | hist) . . (0) . . 2009 AIME I Problems/Problem 12 (→Solution 3)
- 17:17, 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) - 16:31, 27 February 2010 (diff | hist) . . (0) . . 2009 AIME I Problems/Problem 5 (→Solution)