A025974 Expansion of 1/((1-2*x)*(1-4*x)*(1-7*x)*(1-11*x)).

1, 24, 383, 5166, 63993, 756108, 8690611, 98243322, 1099333565, 12223792152, 135381670359, 1495646457318, 16497281164417, 181786417955556, 2001865410394427, 22036025351972754, 242504828325007749, 2668312992107844720, 29356762214354299615, 322961620015828639230

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..900

Index entries for linear recurrences with constant coefficients, signature (24,-193,606,-616).

Formula

a(n) = -4*2^n/45+32*4^n/21-343*7^n/60+1331*11^n/252. - R. J. Mathar, Jun 20 2013

From Wesley Ivan Hurt, Jun 26 2022: (Start)

G.f.: 1/((1-2*x)*(1-4*x)*(1-7*x)*(1-11*x)).

a(n) = 24*a(n-1)-193*a(n-2)+606*a(n-3)-616*a(n-4). (End)

a(n) = (4^(n+1)-2^(n+1))/2+18*a(n-1)-77*a(n-2). - Vincenzo Librandi, Jun 24 2026

Mathematica

CoefficientList[Series[1/((1-2x)(1-4x)(1-7x)(1-11x)), {x, 0, 20}], x] (* Harvey P. Dale, Apr 05 2021 *)

Prog

(Magma) I:=[1, 24]; [n le 2 select I[n] else (4^n-2^n)/2+18*Self(n-1)-77*Self(n-2): n in [1..20]]; // Vincenzo Librandi, Jun 24 2026

Crossrefs

Sequence in context: A023951 A025990 A022565 * A059157 A228406 A087292

Adjacent sequences: A025971 A025972 A025973 * A025975 A025976 A025977

Keyword

nonn,easy

Author

N. J. A. Sloane

Extensions

More terms from Vincenzo Librandi, Jun 24 2026

Status

approved