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A102486 a(n) = 4*a(n-1) - 5*a(n-2).

%I A102486 #29 May 14 2024 03:27:49
%S A102486 2,6,14,26,34,6,-146,-614,-1726,-3834,-6706,-7654,2914,49926,185134,
%T A102486 490906,1037954,1697286,1599374,-2088934,-16352606,-54965754,
%U A102486 -138099986,-277571174,-419784766,-291283194,933791054,5191580186,16097365474,38431560966,73239416494,100799861146
%N A102486 a(n) = 4*a(n-1) - 5*a(n-2).
%C A102486 Inverse binomial transform is 2,4,4,0,-8,-16,-16,.. essentially -A146559(n+3). - _R. J. Mathar_, Apr 07 2022
%D A102486 B. M. E. Moret and H. D. Shapiro, Algorithms from P to NP, Benjamin/Cummings, Vol. 1, 1991; p. 65.
%H A102486 Vincenzo Librandi, <a href="/A102486/b102486.txt">Table of n, a(n) for n = 0..1000</a>
%H A102486 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (4,-5).
%F A102486 G.f.: 2*(1-x)/(1-4*x+5*x^2). [_Colin Barker_, Jan 14 2012]
%p A102486 a := proc(n) option remember; if n = 0 then RETURN(2) end if; if n = 1 then RETURN(6) end if; 4*a(n - 1) - 5*a(n - 2); end proc;
%t A102486 Column[LinearRecurrence[{4,-5},{2,6},40]] (* _Vincenzo Librandi_, Jan 15 2012 *)
%o A102486 (Magma) I:=[2, 6]; [n le 2 select I[n] else 4*Self(n-1)-5*Self(n-2): n in [1..40]]; // _Vincenzo Librandi_, Jan 15 2012
%o A102486 (PARI) Vec(2*(1-x)/(1-4*x+5*x^2)+O(x^99)) \\ _Charles R Greathouse IV_, Jan 15 2012
%Y A102486 Cf. A099456.
%K A102486 sign,easy
%O A102486 0,1
%A A102486 _N. J. A. Sloane_, Feb 25 2005