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a(n) = 2^n + 3^n + 9^n.
1

%I #18 Sep 08 2022 08:45:07

%S 3,14,94,764,6658,59324,532234,4785284,43053538,387440684,3486844474,

%T 31381238804,282430072018,2541867430844,22876797254314,

%U 205891146476324,1853020231964098,16677181828937804,150094635684681754

%N a(n) = 2^n + 3^n + 9^n.

%H Vincenzo Librandi, <a href="/A074531/b074531.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (14,-51,54).

%F From _Mohammad K. Azarian_, Dec 27 2008: (Start)

%F G.f.: 1/(1-2*x) + 1/(1-3*x) + 1/(1-9*x).

%F E.g.f.: exp(2*x) + exp(3*x) + exp(9*x). (End)

%t Table[2^n + 3^n + 9^n, {n, 0, 20}]

%t LinearRecurrence[{14,-51,54},{3,14,94},20] (* _Harvey P. Dale_, Nov 29 2019 *)

%o (Magma) [2^n + 3^n + 9^n: n in [0..25]]; // _Vincenzo Librandi_, Jun 11 2011

%Y Cf. A001550, A001576, A034513, A001579, A074501 - A074580.

%K easy,nonn

%O 0,1

%A _Robert G. Wilson v_, Aug 23 2002