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A074609
a(n) = 3^n + 8^n.
3
2, 11, 73, 539, 4177, 33011, 262873, 2099339, 16783777, 134237411, 1073800873, 8590111739, 68720008177, 549757408211, 4398051294073, 35184386437739, 281475019757377, 2251799942825411, 18014398896902473, 144115189238117339
OFFSET
0,1
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
MATHEMATICA
Table[3^n + 8^n, {n, 0, 25}]
LinearRecurrence[{11, -24}, {2, 11}, 30] (* Harvey P. Dale, Mar 10 2015 *)
PROG
(Magma) [3^n+8^n: n in [0..30]]; // G. C. Greubel, Jan 14 2024
(SageMath) [3^n+9^n for n in range(31)] # G. C. Greubel, Jan 14 2024
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Aug 25 2002
STATUS
approved