OFFSET
0,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (-1,12).
FORMULA
a(n) = -a(n-1) + 12*a(n-2), a(0) = 1, a(1) = -3, for n>1.
a(n) = Sum_{0<=k<=n} A112555(n,k)*(-4)^k.
G.f.: (1-2x)/(1+x-12x^2).
E.g.f.: (1/7)*(exp(3*x) + 6*exp(-4*x)). - G. C. Greubel, Apr 24 2016
MATHEMATICA
LinearRecurrence[{-1, 12}, {1, -3}, 100] (* G. C. Greubel, Apr 24 2016 *)
PROG
(PARI) a(n)= (3^n+6*(-4)^n)/7;
for(n=0, 33, print1(a(n), ", "));
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Philippe Deléham, Oct 05 2009
EXTENSIONS
a(5) corrected by Tilman Neumann, Dec 31 2010
STATUS
approved