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%I #28 Sep 08 2022 08:44:30
%S -1,-2,-2,10,94,538,2638,12010,52414,222778,930478,3840010,15714334,
%T 63920218,258869518,1045044010,4208873854,16921588858,67944635758,
%U 272553384010,1092538058974,4377125804698,17529423925198
%N a(n) = 4^n - 2*3^n.
%H Vincenzo Librandi, <a href="/A002250/b002250.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 (7,-12).
%F G.f.: -(1-5*x)/((1-3*x)*(1-4*x)). - _Bruno Berselli_, Jan 25 2011
%F a(n) = 7*a(n-1) - 12*a(n-2) for n>1. - _Bruno Berselli_, Jan 25 2011
%t Table[4^n - 2 3^n, {n, 0, 30}] (* or *) CoefficientList[Series[-(1 - 5 x) / ((1 - 3 x) (1 - 4 x)), {x, 0, 40}], x] (* _Vincenzo Librandi_, Jun 20 2013 *)
%o (Magma) [4^n-2*3^n: n in [0..30]]; // _Vincenzo Librandi_, Jun 20 2013
%o (PARI) a(n)=4^n-2*3^n \\ _Charles R Greathouse IV_, Jun 23 2020
%Y Cf. A005061, A000244.
%K sign,easy
%O 0,2
%A _N. J. A. Sloane_
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