A375164 Expansion of 1/((1 - x)^4 - 2*x^4).

1, 4, 10, 20, 37, 72, 156, 360, 829, 1852, 4030, 8684, 18793, 41040, 90168, 198288, 435097, 952372, 2082226, 4553348, 9964621, 21819672, 47786580, 104640120, 229084309, 501462508, 1097691238, 2402967260, 5260655953, 11517047712, 25213815408, 55198566432

Offset

0,2

Links

Table of n, a(n) for n=0..31.

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,1).

Formula

a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) + a(n-4).

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

Prog

(PARI) my(N=40, x='x+O('x^N)); Vec(1/((1-x)^4-2*x^4))

Crossrefs

Cf. A000129, A375165.

Sequence in context: A301170 A188280 A295950 * A038420 A008254 A301178

Adjacent sequences: A375161 A375162 A375163 * A375165 A375166 A375167

Keyword

nonn,easy

Author

Seiichi Manyama, Aug 05 2024

Status

approved