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

A371825

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

Terms

    a(0) =1a(1) =3a(2) =18a(3) =146a(4) =1510a(5) =19302a(6) =296520a(7) =5339924a(8) =110447046a(9) =2581169510a(10) =67274981356

External references