A074606 a(n) = 3^n + 5^n.
2, 8, 34, 152, 706, 3368, 16354, 80312, 397186, 1972808, 9824674, 49005272, 244672066, 1222297448, 6108298594, 30531927032, 152630937346, 763068593288, 3815084686114, 19074648589592, 95370918425026, 476847618556328
Offset: 0
Links
- Vincenzo Librandi, Table of n, a(n) for n = 0..200
- Index entries for linear recurrences with constant coefficients, signature (8,-15).
Crossrefs
Programs
-
Magma
[3^n + 5^n: n in [0..35]]; // Vincenzo Librandi, Apr 30 2011
-
Mathematica
Table[3^n + 5^n, {n, 0, 25}] -
PARI
a(n)=3^n+5^n \\ Charles R Greathouse IV, Sep 28 2015
-
SageMath
[3^n+5^n for n in range(41)] # G. C. Greubel, Jan 14 2024
Formula
From Mohammad K. Azarian, Jan 11 2009: (Start)
G.f.: 1/(1-3*x) + 1/(1-5*x).
E.g.f.: exp(3*x) + exp(5*x). (End)
a(n) = 8*a(n-1) - 15*a(n-2) with a(0)=2, a(1)=8. - Vincenzo Librandi, Jul 21 2010
a(n) = 2*A081186(n). - R. J. Mathar, Mar 10 2022