Is there a way to find no of perfect matchings in a complete graph Kn where n could be either even or odd..?
if n is odd then perfect matching 0. because in perfect matching degree of each vertex must be 1, which is not possible if n is odd.
and if n is even then num of perfect matching in K2n=( 2n! ) / ( 2^n * n! )
explain how K2n=( 2n! ) / ( 2^n * n! )
X->YZ , Y->XZ , ...