OFFSET
0,1
COMMENTS
The subsequence of (positive or negative) primes begins: -3, -5, -7, -5, 17, no more through the composite a(116) (which is near 2.2*10^55). - Jonathan Vos Post, Jul 03 2012
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (5,-6).
FORMULA
G.f.: ( -3+10*x ) / ( (3*x-1)*(2*x-1) ). - R. J. Mathar, Jul 07 2012
a(n) = 5*a(n-1) - 6*a(n-2) for n>1. - Vincenzo Librandi, Jun 18 2014
MATHEMATICA
Table[3^n - 2^(n+2), {n, 0, 30}] (* or *) CoefficientList[Series[(-3 + 10 x)/((3 x - 1) (2 x - 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Jun 17 2014 *)
PROG
(Magma) [3^n - 2^(n+2): n in [0..30]]; // Vincenzo Librandi, Jun 18 2014
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Alex Ratushnyak, Jul 03 2012
STATUS
approved