A074616 a(n) = 5^n + 7^n.

2, 12, 74, 468, 3026, 19932, 133274, 901668, 6155426, 42306732, 292240874, 2026154868, 14085427826, 98109713532, 684326588474, 4778079088068, 33385518460226, 233393453440332, 1632228295176074, 11417968671701268

Offset: 0

Author

Robert G. Wilson v, Aug 26 2002

Keywords

• easy
• nonn

Links

• Index entries for linear recurrences with constant coefficients, signature (12,-35).

Crossrefs

Cf. A000051, A034472, A052539, A034474, A062394, A034491, A062395, A062396, A007689, A063376, A063481, A074600..A074624.

Programs

Mathematica

Table[5^n + 7^n, {n, 0, 20}]
LinearRecurrence[{12,-35},{2,12},20] (* Harvey P. Dale, Aug 26 2021 *)

Formula

From Mohammad K. Azarian, Jan 11 2009: (Start)

G.f.: 1/(1-5*x) + 1/(1-7*x).

E.g.f.: e^(5*x) + e^(7*x). (End)

a(n) = 12*a(n-1) - 35*a(n-2) with a(0)=2, a(1)=12. - Vincenzo Librandi, Jul 21 2010