A074609 a(n) = 3^n + 8^n.

2, 11, 73, 539, 4177, 33011, 262873, 2099339, 16783777, 134237411, 1073800873, 8590111739, 68720008177, 549757408211, 4398051294073, 35184386437739, 281475019757377, 2251799942825411, 18014398896902473, 144115189238117339

Offset: 0

Author

Robert G. Wilson v, Aug 25 2002

Keywords

• easy
• nonn

Links

• G. C. Greubel, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (11,-24).

Crossrefs

Cf. A000051, A007689, A034472, A034474, A034491, A052539, A062394.

Cf. A062395, A062396, A063376, A063481, A074600..A074624.

Programs

Magma

[3^n+8^n: n in [0..30]]; // G. C. Greubel, Jan 14 2024

Mathematica

Table[3^n + 8^n, {n, 0, 25}]
LinearRecurrence[{11,-24},{2,11},30] (* Harvey P. Dale, Mar 10 2015 *)

SageMath

[3^n+9^n for n in range(31)] # G. C. Greubel, Jan 14 2024

Formula

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

G.f.: 1/(1-3*x) + 1/(1-8*x).

E.g.f.: exp(3*x) + exp(8*x). (End)

a(n) = 11*a(n-1) - 24*a(n-2) with a(0)=2, a(1)=11. - Vincenzo Librandi, Jul 21 2010