The Friendship Theorem - You Always Have 3 Friends Or 3 Strangers At A Party

Описание: In a group of 6 people, you might find that some people are friends on Facebook, or you might find out that no one is friends on Facebook. Show that there is always a group of 3 people in which either: (a) all 3 people are mutual friends or (b) the 3 people are mutual strangers (no one is friends on Facebook). The video presents a solution to this problem which is also known as the Friendship Theorem and is an example of Ramsey Theory (a field which studies the conditions in which order arises).

Blog post: http://wp.me/p6aMk-4Ks

Ramsey Theory Friendship Theorem references
https://plus.maths.org/content/friend...
https://en.wikipedia.org/wiki/Theorem...
http://mathgardenblog.blogspot.com/20...

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