login
a(n) = 4^n + 5^n + 9^n.
1

%I #15 Sep 08 2022 08:45:07

%S 3,18,122,918,7442,63198,551162,4877478,43502882,389635758,3497598602,

%T 31434082038,282690454322,2543153640318,22883164406042,

%U 205922723414598,1853177071709762,16677961818988878,150098518713741482

%N a(n) = 4^n + 5^n + 9^n.

%H Vincenzo Librandi, <a href="/A074564/b074564.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (18,-101,180).

%F From _Mohammad K. Azarian_, Dec 30 2008: (Start)

%F G.f.: 1/(1-4*x) + 1/(1-5*x) + 1/(1-9*x).

%F E.g.f.: exp(4*x) + exp(5*x) + exp(9*x). (End)

%t Table[4^n + 5^n + 9^n, {n, 0, 20}]

%o (Magma) [4^n + 5^n + 9^n: n in [0..20]]; // _Vincenzo Librandi_, Aug 25 2011

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

%K easy,nonn

%O 0,1

%A _Robert G. Wilson v_, Aug 23 2002