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The Friendship Theorem

Martin Liebeck

Date Icon Week 6, Monday 27 January MT 2020
Time Icon 8:15pm

This theorem that tells you that if you go to a party where any two people have exactly one mutual acquaintance, then there is someone who knows everybody. Apart from its obvious fundamental applications to the theory of going to parties, it also has a wonderful proof which uses a completely different and unexpected part of maths. The talk should be comprehensible to all undergraduates, including those who have just started.