OFFSET
0,3
COMMENTS
The coefficients of the recursion for a(n) are given by the 9th row of A145152.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (9, -36, 84, -125, 118, -56, -20, 61, -55, 28, -8, 1).
FORMULA
a(n) = [9, -36, 84, -125, 118, -56, -20, 61, -55, 28, -8, 1] * [a(n-1), ..., a(n-12)].
MAPLE
col:= proc(k) local l, j, M, n; l:= `if`(k=0, [1, 0, 0, 1], [seq(coeff( -(1-x-x^4) *(1-x)^(k-1), x, j), j=1..k+3)]); M:= Matrix(nops(l), (i, j)-> if i=j-1 then 1 elif j=1 then l[i] else 0 fi); `if`(k=0, n->(M^n)[2, 3], n->(M^n)[1, 2]) end: a:= col(9): seq(a(n), n=0..40);
MATHEMATICA
CoefficientList[Series[x/((1-x-x^4)(1-x)^8), {x, 0, 40}], x] (* or *) LinearRecurrence[{9, -36, 84, -125, 118, -56, -20, 61, -55, 28, -8, 1}, {0, 1, 9, 45, 165, 496, 1297, 3058, 6655, 13586, 26323, 48829}, 40] (* Harvey P. Dale, Feb 22 2012 *)
PROG
(PARI) concat(0, Vec(1/((1-x-x^4)*(1-x)^8)+O(x^99))) \\ Charles R Greathouse IV, Sep 25 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Oct 03 2008
STATUS
approved