A027151 - OEIS

A027151

a(n) = T(n,0) + T(n,1) + ... + T(n,n), T given by A027144.

1, 3, 7, 21, 45, 135, 291, 873, 1881, 5643, 12159, 36477, 78597, 235791, 508059, 1524177, 3284145, 9852435, 21229047, 63687141, 137226717, 411680151, 887047443, 2661142329, 5733964809, 17201894427, 37064931183, 111194793549, 239591481525, 718774444575

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Colin Barker, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (0,6,0,3).

FORMULA

G.f.: (1 + 3*x)*(1 + x^2) / (1 - 6*x^2 - 3*x^4).

a(n) = 6*a(n-2) + 3*a(n-4) for n>3. - Colin Barker, Jan 18 2018

PROG

(PARI) Vec((1 + 3*x)*(1 + x^2) / (1 - 6*x^2 - 3*x^4) + O(x^40)) \\ Colin Barker, Jan 18 2018

CROSSREFS