OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (7,-12).
FORMULA
From Bruno Berselli, Jan 25 2011: (Start)
G.f.: -(1-5*x)/((1-3*x)*(1-4*x)).
a(n) = 7*a(n-1) - 12*a(n-2) for n > 1. (End)
From Elmo R. Oliveira, Sep 15 2024: (Start)
E.g.f.: exp(3*x)*(exp(x) - 2).
MATHEMATICA
Table[4^n - 2 3^n, {n, 0, 30}] (* or *) CoefficientList[Series[-(1 - 5 x) / ((1 - 3 x) (1 - 4 x)), {x, 0, 40}], x] (* Vincenzo Librandi, Jun 20 2013 *)
PROG
(Magma) [4^n-2*3^n: n in [0..30]]; // Vincenzo Librandi, Jun 20 2013
(PARI) a(n)=4^n-2*3^n \\ Charles R Greathouse IV, Jun 23 2020
CROSSREFS
KEYWORD
sign,easy
AUTHOR
STATUS
approved