MathDB

An n\minus{}m society is a group of

n

girls and

m

boys. Prove that there exists numbers

n_0

and

m_0

such that every n_0\minus{}m_0 society contains a subgroup of five boys and five girls with the following property: either all of the boys know all of the girls or none of the boys knows none of the girls.

4

Problems(1)