The Friendship Theorem
Karol Pąk
Formalized Mathematics, Tome 20 (2012), p. 235-237 / Harvested from The Polish Digital Mathematics Library
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In this article we prove the friendship theorem according to the article [1], which states that if a group of people has the property that any pair of persons have exactly one common friend, then there is a universal friend, i.e. a person who is a friend of every other person in the group

Publié le : 2012-01-01
EUDML-ID : urn:eudml:doc:267893 
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     year = {2012},
     pages = {235-237},
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Karol Pąk. The Friendship Theorem. Formalized Mathematics, Tome 20 (2012) pp. 235-237. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_v10037-012-0028-7/

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