Ramsey problem: 3 people in 6 pairwise knowing or strangers

by adityaguharoy, Jan 19, 2018, 11:57 AM

Given any collection of $6$ people. Prove that there is either a collection of $3$ people among them such that they know each other pairwise, or there is a collection of $3$ people among them who are pairwise strangers.

Proof

In the language of arrows
Ramsey
Ramsey Theory
combinatorics

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Come on man I proved this when I was in 8th standard and preparing for rmo

by agrnoob, Jul 16, 2022, 4:01 PM

The oldest, shortest words — "yes" and "no" — are those which require the most thought.

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