A377269 G.f. satisfies A(x) = (1 - 9*x*A(x))^(2/3).

1, -6, 27, -90, 189, 0, -1782, 6318, 0, -90882, 360126, 0, -5985819, 24931800, 0, -446371074, 1912892355, 0, -35840971530, 156454458930, 0, -3022929941616, 13367712796110, 0, -264079216747476, 1179032268616902, 0, -23685874363658232, 106533987128598645, 0

Offset

0,2

Links

Table of n, a(n) for n=0..29.

Index entries for reversions of series

Formula

G.f.: (1/x) * Series_Reversion( x/(1-9*x)^(2/3) ).

a(n) = 9^n * binomial(n/3 - 5/3,n)/(n+1).

Prog

(PARI) a(n) = 9^n*binomial(n/3-5/3, n)/(n+1);

Crossrefs

Cf. A377268.

Sequence in context: A100188 A131985 A125196 * A100189 A052267 A038166

Adjacent sequences: A377266 A377267 A377268 * A377270 A377271 A377272

Keyword

sign,easy

Author

Seiichi Manyama, Oct 22 2024

Status

approved