On a property of the $n$-dimensional cube

We show that in any subset of the vertices of $n$-dimensional cube that contains at least $2^{n-1}+1$ vertices ($n\geq 4$), there are four vertices that induce a claw, or there are eight vertices that induce the cycle of length eight.

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[2]  Frank Harary,et al.  Graph Theory , 2016 .