# The Friendship Theorem

Formalized Mathematics (2012)

- Volume: 20, Issue: 3, page 235-237
- ISSN: 1426-2630

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topKarol Pąk. "The Friendship Theorem." Formalized Mathematics 20.3 (2012): 235-237. <http://eudml.org/doc/267893>.

@article{KarolPąk2012,

abstract = {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},

author = {Karol Pąk},

journal = {Formalized Mathematics},

keywords = {universal friend},

language = {eng},

number = {3},

pages = {235-237},

title = {The Friendship Theorem},

url = {http://eudml.org/doc/267893},

volume = {20},

year = {2012},

}

TY - JOUR

AU - Karol Pąk

TI - The Friendship Theorem

JO - Formalized Mathematics

PY - 2012

VL - 20

IS - 3

SP - 235

EP - 237

AB - 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

LA - eng

KW - universal friend

UR - http://eudml.org/doc/267893

ER -

## References

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