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a(n) = 11^n + 7^n - 1.
17

%I #17 Sep 08 2022 08:45:40

%S 1,17,169,1673,17041,177857,1889209,20310713,220123681,2398301297,

%T 26219899849,287288997353,3152269663921,34619601154337,

%U 380428056656089,4181995730925593,45982962794141761,505679659013280977

%N a(n) = 11^n + 7^n - 1.

%H G. C. Greubel, <a href="/A155658/b155658.txt">Table of n, a(n) for n = 0..958</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (19,-95,77).

%F G.f.: 1/(1-11*x) + 1/(1-7*x) - 1/(1-x).

%F E.g.f.: exp(11*x) + exp(7*x) - exp(x).

%F a(n) = 18*a(n-1)-77*a(n-2)-60 with a(0)=1, a(1)=17. - _Vincenzo Librandi_, Jul 21 2010

%t Table[11^n+7^n-1, {n,0,20}] (* _G. C. Greubel_, Nov 18 2018 *)

%o (PARI) a(n)=11^n+7^n-1 \\ _Charles R Greathouse IV_, Jun 11 2015

%o (Magma) [11^n+7^n-1: n in [0..20]]; // _G. C. Greubel_, Nov 18 2018

%o (Sage) [11^n+7^n-1 for n in range(20)] # _G. C. Greubel_, Nov 18 2018

%o (GAP) List([0..20], n -> 11^n+7^n-1); # _G. C. Greubel_, Nov 18 2018

%Y Cf. A155638, A155639, A155640, A155641, A155642, A155643, A155644, A155645, A155646, A155647, A155648, A155649, A155650, A155651, A155652, A155653, A155654, A155655, A155656, A155657.

%K nonn,easy

%O 0,2

%A _Mohammad K. Azarian_, Jan 31 2009