A364592 G.f. satisfies A(x) = 1/(1-x) + x*(1-x)*A(x)^4.

1, 2, 8, 49, 365, 3001, 26193, 238119, 2230151, 21368167, 208459419, 2063563791, 20675793627, 209277092776, 2136720896514, 21979879393677, 227582114799201, 2369983696546858, 24806423607475896, 260829829404493787, 2753744691645428399

Offset

0,2

Links

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

Formula

a(n) = Sum_{k=0..n} binomial(n+k,2*k) * binomial(4*k,k) / (3*k+1).

Prog

(PARI) a(n) = sum(k=0, n, binomial(n+k, 2*k)*binomial(4*k, k)/(3*k+1));

Crossrefs

Cf. A014137, A188687.

Cf. A364594, A364596.

Sequence in context: A279109 A355667 A366239 * A183070 A032116 A088181

Adjacent sequences: A364589 A364590 A364591 * A364593 A364594 A364595

Keyword

nonn,easy

Author

Seiichi Manyama, Jul 29 2023

Status

approved