OFFSET
0,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (15,-62,72).
FORMULA
From Mohammad K. Azarian, Dec 27 2008: (Start)
G.f.: 1/(1-2*x) + 1/(1-4*x) + 1/(1-9*x).
E.g.f.: exp(2*x) + exp(4*x) + exp(9*x). (End)
MATHEMATICA
Table[2^n + 4^n + 9^n, {n, 0, 20}]
PROG
(Magma) [2^n + 4^n + 9^n: n in [0..25]]; // Vincenzo Librandi, Jun 11 2011
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Aug 23 2002
STATUS
approved