A130019 a(n+2) = 6*a(n+1) + (-11 + n)*a(n) + (6 - 2*n)*a(n-1) for n >= 1.

0, 0, 1, 6, 27, 114, 483, 2106, 9537, 44934, 219933, 1115286, 5842707, 31537314, 174991443, 996169146, 5808168297, 34633891734, 210943794093, 1310837402646, 8302614222507, 53552183145234, 351468155184003, 2345436650546106

Offset

0,4

Links

Table of n, a(n) for n=0..23.

Formula

a(n+2) = 6*a(n+1) + (-11 + n)*a(n) + (6 - 2*n)*a(n-1) for n >= 1. \\ Jianing Song, Oct 10 2018

Mathematica

M[n_] := {{0, 1, 0}, {0, 0, 1}, {6 - 2*n, -11 + n, 6}}
v[0] = {0, 0, 1};
v[n_] := v[n] = M[n].v[n - 1]
a = Table[v[n][[1]], {n, 0, 30}]

Prog

(PARI) M(n) = [0, 1, 0; 0, 0, 1; 6 - 2*n, -11 + n, 6];
T(n) = if(n==0, [0; 0; 1], M(n)*T(n-1))
a(n) = T(n)[1, 1] \\ Jianing Song, Oct 10 2018

Crossrefs

Sequence in context: A079742 A291232 A171475 * A196919 A049651 A109114

Adjacent sequences: A130016 A130017 A130018 * A130020 A130021 A130022

Keyword

nonn,easy

Author

Roger L. Bagula, Jun 16 2007

Extensions

Edited, new name, and offset corrected by Jianing Song, Oct 10 2018

Status

approved