a(n) = Sum_{k=0..n} Stirling2(2*n+k, k) * C(n, k).

A242019

a(n) = Sum_{k=0..n} Stirling2(2*n+k, k) * C(n, k).

Terms

    a(0) =1a(1) =1a(2) =33a(3) =3409a(4) =728575a(5) =265362370a(6) =147228369351

External references