742016

Appears in sequences

• From the enumeration of corners.at n=15A006332
• If X_1,...,X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 4-subsets of X containing none of X_i, (i=1,...,n).at n=30A130810
• E.g.f.: Sum_{n>=0} cosh(n*x) * tanh(x)^n.at n=8A211209
• a(n) = n*(n + 1)*(n + 2)*(9*n - 7)/12.at n=31A264852