A366241 G.f. A(x) satisfies A(x) = 1 + x + x*(1 + x)^4*A(x)^3.

1, 2, 10, 72, 552, 4593, 40185, 364413, 3395217, 32305005, 312589540, 3066565720, 30430287693, 304907935707, 3080617021926, 31349533179726, 321038696185371, 3305935381202847, 34211612434972446, 355605873560512974, 3710978684625678870

Offset

0,2

Links

Table of n, a(n) for n=0..20.

Formula

a(n) = Sum_{k=0..n} binomial(6*k+1,n-k) * binomial(3*k,k)/(2*k+1).

Prog

(PARI) a(n) = sum(k=0, n, binomial(6*k+1, n-k)*binomial(3*k, k)/(2*k+1));

Crossrefs

Cf. A364336, A366239, A366240.

Cf. A366222.

Sequence in context: A060842 A245834 A271214 * A321446 A111554 A177384

Adjacent sequences: A366238 A366239 A366240 * A366242 A366243 A366244

Keyword

nonn

Author

Seiichi Manyama, Oct 05 2023

Status

approved