A025949 Expansion of 1/((1-2*x)*(1-3*x)*(1-8*x)*(1-10*x)).

1, 23, 353, 4579, 54393, 613419, 6692161, 71391683, 749696585, 7783261915, 80123162769, 819556503987, 8342165636377, 84594465902411, 855327149649377, 8628331464477091, 86883794517646569, 873641784546629307, 8774848561589339185, 88055931348363496595, 883018879353854059961, 8849865320531670217003

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (23,-176,508,-480).

Formula

a(n) = -2^n/6+27*3^n/35-128*8^n/15+125*10^n/14. - R. J. Mathar, Jun 20 2013

a(n) = 3^(n+1)-2^(n+1)+18*a(n-1)-80*a(n-2). - Vincenzo Librandi, May 13 2026

Mathematica

a[0]=1; a[1]=23; a[n_]:=a[n]=3^(n+1)-2^(n+1)+18*a[n-1]-80*a[n-2]; Table[a[n], {n, 0, 21}] (* Vincenzo Librandi, May 13 2026 *)

Prog

(Magma) I:=[1, 23]; [n le 2 select I[n] else 3^n-2^n+18*Self(n-1)-80*Self(n-2): n in [1..22]]; // Vincenzo Librandi, May 13 2026

Crossrefs

Sequence in context: A028030 A022454 A142617 * A025969 A020579 A021914

Adjacent sequences: A025946 A025947 A025948 * A025950 A025951 A025952

Keyword

nonn,easy

Author

N. J. A. Sloane

Extensions

More terms from Vincenzo Librandi, May 13 2026

Status

approved