OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (26,-221,676,-480).
FORMULA
a(n) = (3*12^(n+3) - 11*8^(n+3) + 11*5^(n+3) - 3)/924. - Yahia Kahloune, Jun 29 2013
a(0)=1, a(1)=26, a(2)=455, a(3)=6760; for n>3, a(n) = 26*a(n-1) -221*a(n-2) +676*a(n-3) -480*a(n-4). - Vincenzo Librandi, Jul 12 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - x) (1 - 5 x) (1 - 8 x) (1 - 12 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 12 2013 *)
PROG
(Magma) I:=[1, 26, 455, 6760]; [n le 4 select I[n] else 26*Self(n-1)-221*Self(n-2)+676*Self(n-3)-480*Self(n-4): n in [1..25]]; /* or */ m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-5*x)*(1-8*x)*(1-12*x)))); // Vincenzo Librandi, Jul 12 2013
(PARI) x='x+O('x^30); Vec(1/((1-x)*(1-5*x)*(1-8*x)*(1-12*x))) \\ G. C. Greubel, Jul 25 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved