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%I #21 Sep 14 2019 16:28:20
%S 1,1,0,2,3,-1,2,8,-3,-3,20,-2,-25,43,22,-92,65,137,-248,-6,523,-489,
%T -534,1536,-443,-2603,3516,1718,-8721,5315,12158,-22756,-1527,47073,
%U -43984,-50126,138131,-37841,-238382,314104,162701,-790867,465508,1116270,-2047241,-185253,4279782,-3909228
%N Expansion of (1-x)^(-1)/(1+x^2-2*x^3).
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (1,-1,3,-2).
%F a(n) = a(n-1) - a(n-2) + 3 a(n-3) - 2 a(n-4), with a(0) = a(1) = 1, a(2) = 0 and a(3) = 2. - _Jean-François Alcover_, Apr 06 2016
%F a(n) = n+1 - a(n-1) - 2*a(n-2), with a(0) = a(1) = 1. - _Michel Marcus_, Apr 06 2016
%t RecurrenceTable[{a[1] == a[2] == 1, a[n] == n - a[n-1] - 2 a[n-2]}, a, {n, 50}] (* _Jean-François Alcover_, Apr 06 2016 *)
%t LinearRecurrence[{1,-1,3,-2},{1,1,0,2},50] (* _Harvey P. Dale_, Sep 14 2019 *)
%o (PARI) Vec(1/((1-x)*(1+x^2-2*x^3)) + O(x^60)) \\ _Michel Marcus_, Apr 06 2016
%K sign,easy
%O 0,4
%A _N. J. A. Sloane_, Nov 17 2002