A376804 Expansion of 1/((1 - x)^3 - 9*x^3)^(1/3).

1, 1, 1, 4, 13, 31, 79, 232, 673, 1891, 5401, 15742, 45958, 134122, 393394, 1159432, 3425101, 10137985, 30079405, 89437960, 266389615, 794667325, 2374097485, 7102303240, 21272892055, 63788000461, 191471030791, 575287348546, 1730027151334, 5206918491298

Offset

0,4

Links

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

Formula

a(n) = Sum_{k=0..floor(n/3)} (-9)^k * binomial(-1/3,k) * binomial(n,n-3*k).

Prog

(PARI) my(N=30, x='x+O('x^N)); Vec(1/((1-x)^3-9*x^3)^(1/3))

Crossrefs

Cf. A098536, A376802, A376803.

Sequence in context: A097122 A116411 A333047 * A106337 A027998 A367010

Adjacent sequences: A376801 A376802 A376803 * A376805 A376806 A376807

Keyword

nonn

Author

Seiichi Manyama, Oct 04 2024

Status

approved