a(n) = n!*Sum_{k=0..n} binomial(2*n,n-k)*n^k/k!.

A295385

a(n) = n!*Sum_{k=0..n} binomial(2*n,n-k)*n^k/k!.

Terms

    a(0) =1a(1) =3a(2) =32a(3) =579a(4) =14736a(5) =483115a(6) =19376928a(7) =918980139a(8) =50306339072

External references