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a(n) = 8^n + 9^n.
39

%I #29 Mar 13 2023 03:14:52

%S 2,17,145,1241,10657,91817,793585,6880121,59823937,521638217,

%T 4560526225,39970994201,351149013217,3091621642217,27274838966065,

%U 241075504183481,2134495165562497,18928981513351817,168109033806481105

%N a(n) = 8^n + 9^n.

%H G. C. Greubel, <a href="/A074624/b074624.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (17,-72).

%F From _Mohammad K. Azarian_, Jan 11 2009: (Start)

%F G.f.: 1/(1-8*x) + 1/(1-9*x).

%F E.g.f.: exp(8*x) + exp(9*x). (End)

%F a(n) = 17*a(n-1) - 72*a(n-2) with a(0)=2, a(1)=17. - _Vincenzo Librandi_, Jul 21 2010

%p seq(8^n+9^n,n=0..30); # _Robert Israel_, Mar 11 2023

%t Table[8^n + 9^n, {n, 0, 20}]

%o (PARI) a(n)=8^n+9^n \\ _Charles R Greathouse IV_, Apr 08 2016

%o (Magma) [8^n+9^n: n in [0..30]]; // _G. C. Greubel_, Mar 11 2023

%o (SageMath) [8^n+9^n for n in range(31)] # _G. C. Greubel_, Mar 11 2023

%Y Cf. A007689, A034472, A063376, A063481, A074600..A074623.

%K easy,nonn

%O 0,1

%A _Robert G. Wilson v_, Aug 26 2002