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%I #12 Jun 08 2020 10:44:43
%S 1,-1,3,-6,14,-30,67,-147,325,-716,1580,-3484,7685,-16949,37383,
%T -82450,181850,-401082,884615,-1951079,4303241,-9491096,20933272,
%U -46169784,101830665,-224594601,495358987,-1092548638,2409691878,-5314742742,11722034123,-25853760123,57022262989,-125766560100
%N Expansion of (1-x)^(-1)/(1+2*x+x^3).
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (-1,2,-1,1).
%F a(n)=-a(n-1)+2*a(n-2)-a(n-3)+a(n-4). - _N-E. Fahssi_, Mar 29 2008
%F a(n) -a(n-1) = (-1)^n*A008998(n). - _R. J. Mathar_, Jun 08 2020
%o (PARI) Vec((1-x)^(-1)/(1+2*x+x^3)+O(x^99)) \\ _Charles R Greathouse IV_, Sep 27 2012
%K sign,easy
%O 0,3
%A _N. J. A. Sloane_, Nov 17 2002