OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (24,-173,366,-216).
FORMULA
a(n) = (28*12^(n+3) - 55*9^(n+3) + 132*2^(n+3) - 105)/9240. - Yahia Kahloune, Jul 07 2013
a(0)=1, a(1)=24, a(2)=403, a(3)=5886; for n>3, a(n) = 24*a(n-1) -173*a(n-2) +366*a(n-3) -216*a(n-4). - Vincenzo Librandi, Jul 09 2013
a(0)=1, a(1)=24; for n>1, a(n) = 21*a(n-1) -108*a(n-2) +2^n -1. - Vincenzo Librandi, Jul 09 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - x) (1 - 2 x) (1 - 9 x) (1 -12 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 09 2013 *)
PROG
(Magma) I:=[1, 24, 403, 5886]; [n le 4 select I[n] else 24*Self(n-1)-173*Self(n-2)+366*Self(n-3)-216*Self(n-4): n in [1..25]]; /* or */ m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-2*x)*(1-9*x)*(1-12*x)))); // Vincenzo Librandi, Jul 09 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved