A063396 T(3,n) with T(n,m) as in A063394.

1, 15, 47, 131, 343, 863, 2111, 5055, 11903, 27647, 63487, 144383, 325631, 729087, 1622015, 3588095, 7897087, 17301503, 37748735, 82051071, 177733631, 383778815, 826277887, 1774190591, 3800039423, 8120172543, 17314086911, 36842766335, 78248935423

Offset: 0

Author

Floor van Lamoen, Jul 16 2001

Keywords

• nonn
• easy

Links

• Colin Barker, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (7,-18,20,-8)

Crossrefs

Cf. A063394, A063397, A063398.

Programs

Mathematica

Join[{1},LinearRecurrence[{7,-18,20,-8},{15,47,131,343},30]] (* Harvey P. Dale, Jul 31 2014 *)

PARI

Vec(-(20*x^4-52*x^3+40*x^2-8*x-1)/((x-1)*(2*x-1)^3) + O(x^100)) \\ Colin Barker, May 27 2015

Formula

For n>0, 1/4 * [(n+1)(n+2)2^n + 10(n+1)2^n + 6*2^n - 4]. - Ralf Stephan, May 08 2004

G.f.: -(20*x^4-52*x^3+40*x^2-8*x-1) / ((x-1)*(2*x-1)^3). - Colin Barker, May 27 2015