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Ramsey’s numbers

mathematics
Also known as: Ramsey’s theorem

Quick Summary

Ramsey's numbers, a concept in combinatorics, deal with the existence of specific substructures within larger sets. Developed by mathematician Frank Plumpton Ramsey, the core idea is that in any sufficiently large set, a certain pattern is guaranteed to exist.

For example, consider a group of people at a party. If there are enough people, there must be either a subgroup of a certain size where everyone knows each other, or a subgroup of a certain size where no one knows each other. While the existence of these numbers is proven, their exact values are known only for a few specific cases, such as N2(3, 3) = 6. This area of mathematics explores "problems of choice" and guarantees the presence of order within disorder.1

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