A171196 G.f. satisfies A(x) = 1/(1 - x*A(2x)^6).

1, 1, 13, 397, 23261, 2532093, 520285021, 206632208765, 161306955003037, 249753449538341821, 770275887324912000733, 4741871606773351738426877, 58325180751309642789169099037, 1434100517517383561901937569640509

Offset

0,3

Links

Seiichi Manyama, Table of n, a(n) for n = 0..79

Formula

a(n) ~ c * 2^(n*(n+1)/2) * 3^n, where c = 0.363484431362432363073577975298028185297326... - Vaclav Kotesovec, Nov 03 2021

Mathematica

nmax = 15; A[_] = 0; Do[A[x_] = 1/(1 - x*A[2*x]^6) + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x] (* Vaclav Kotesovec, Nov 03 2021 *)

Prog

(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0, n, A=1/(1-x*subst(A, x, 2*x)^6) ); polcoeff(A, n)}

Crossrefs

Cf. A015083, A171192-A171195, A171197, A171198.

Sequence in context: A203972 A013527 A009010 * A286189 A280553 A162446

Adjacent sequences: A171193 A171194 A171195 * A171197 A171198 A171199

Keyword

nonn

Author

Paul D. Hanna, Dec 05 2009

Status

approved