A376282 G.f. satisfies A(x) = (1 + 9*x*A(x)^7)^(1/3).

1, 3, 54, 1368, 40365, 1299078, 44223732, 1565864784, 57079952046, 2127818007315, 80742077597610, 3108398557803480, 121107814518484872, 4766365291226837508, 189209375036491438800, 7567095678024459993120, 304603864960375133224533, 12331716699093681951702810

Offset

0,2

Links

Table of n, a(n) for n=0..17.

Formula

a(n) = 9^n * binomial(7*n/3 + 1/3,n)/(7*n+1).

Prog

(PARI) a(n) = 9^n*binomial(7*n/3+1/3, n)/(7*n+1);

Crossrefs

Cf. A004987, A008931, A078532, A245114, A376636.

Sequence in context: A222203 A224051 A355365 * A317663 A323325 A224304

Adjacent sequences: A376279 A376280 A376281 * A376283 A376284 A376285

Keyword

nonn

Author

Seiichi Manyama, Oct 23 2024

Status

approved