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%I #11 Apr 08 2016 03:10:20
%S 1,-4,-24,-104,-424,-1704,-6824,-27304,-109224,-436904,-1747624,
%T -6990504,-27962024,-111848104,-447392424,-1789569704,-7158278824,
%U -28633115304,-114532461224,-458129844904,-1832519379624,-7330077518504
%N a(n) = (8-5*4^n)/3.
%H G. C. Greubel, <a href="/A165752/b165752.txt">Table of n, a(n) for n = 0..500</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (5,-4).
%F a(n) = 4*a(n-1) - 8, a(0)=1.
%F a(n) = 5*a(n-1) - 4*a(n-2), a(0)=1, a(1)=-4, for n>1.
%F G.f.: (1-9x)/(1-5x+4x^2).
%F a(n) = Sum_{0<=k<=n} A112555(n,k)*(-5)^(n-k).
%F a(n) = (-4)*A020989(n-1).
%F E.g.f.: (1/3)*(8*exp(x) - 5*exp(4*x)). - _G. C. Greubel_, Apr 07 2016
%t (8-5*4^Range[0,30])/3 (* or *) LinearRecurrence[{5,-4},{1,-4},30] (* _Harvey P. Dale_, Jan 10 2016 *)
%o (PARI) x='x+O('x^99); Vec((1-9*x)/(1-5*x+4*x^2)) \\ _Altug Alkan_, Apr 07 2016
%K easy,sign
%O 0,2
%A _Philippe Deléham_, Sep 26 2009
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