G.f.: Sum_{n>=0} x^n / (1-2*x)^(2*n+1) * [Sum_{k=0..n} C(n,k)^2 * 2^k * x^k] * [Sum_{k=0..n} C(n,k)^2 * 3^k * x^k].
A246056
G.f.: Sum_{n>=0} x^n / (1-2*x)^(2*n+1) * [Sum_{k=0..n} C(n,k)^2 * 2^k * x^k] * [Sum_{k=0..n} C(n,k)^2 * 3^k * x^k].
Terms
- a(0) =1a(1) =3a(2) =16a(3) =99a(4) =681a(5) =4950a(6) =37303a(7) =288399a(8) =2272318a(9) =18167553a(10) =146950227a(11) =1199921310a(12) =9875193549a(13) =81811617237a(14) =681621711306
External references
- oeis: A246056