a(n) = Sum_{k=0..n} n^k * binomial(2*n,2*k).
A333990
a(n) = Sum_{k=0..n} n^k * binomial(2*n,2*k).
Terms
- a(0) =1a(1) =2a(2) =17a(3) =208a(4) =3281a(5) =62976a(6) =1419193a(7) =36643328a(8) =1064876737a(9) =34359869440
External references
- oeis: A333990