Difference between revisions of "2007 IMO Problems/Problem 3"

(New page: <h2>Problem</h2> In a mathematical competition some competitors are friends. Friendship is always mutual. Call a group of competitors a clique if each two of them are friends. (In particul...)
 
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<h2>Solution</h2>
 
<h2>Solution</h2>
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The Nottingham Tuesday Club members solved this problem and published their solution in their website. The solution is a PDF document.
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<ul>
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<li><a href="http://sneezy.cs.nott.ac.uk/tmc/wp-content/uploads/2007/10/cliqueproblem.pdf">TMC Solution to Problem 3, IMO 2007</a></li>
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<li><a href="http://sneezy.cs.nott.ac.uk/tmc">TMC webpage</a></li>
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</ul>

Revision as of 10:01, 28 October 2007

Problem

In a mathematical competition some competitors are friends. Friendship is always mutual. Call a group of competitors a clique if each two of them are friends. (In particular, any group of fewer than two competitors is a clique.) The number of members of a clique is called its size. Given that, in this competition, the largest size of a clique is even, prove that the competitors can be arranged in two rooms such that the largest size of a clique contained in one room is the same as the largest size of a clique contained in the other room.

Solution

The Nottingham Tuesday Club members solved this problem and published their solution in their website. The solution is a PDF document.