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Expansion of 1/((1+x)^3-x^4).
1

%I #8 Jul 16 2018 19:29:42

%S 1,-3,6,-10,16,-27,49,-92,172,-316,573,-1035,1874,-3406,6204,-11303,

%T 20577,-37432,68072,-123800,225193,-409683,745342,-1355970,2466760,

%U -4487395,8163217,-14850196,27015092,-49145300,89404037,-162641499,295872778,-538243174,979156724,-1781254927,3240410561

%N Expansion of 1/((1+x)^3-x^4).

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (-3,-3,-1,1).

%F G.f.: 1/(1+3x+3x^2+x^3-x^4); a(n)=sum{k=0..n+4, (-1)^(n-k)*C(n+4, k)*sum{j=0..floor(k/4), C(k-3j, j)}}.

%t LinearRecurrence[{-3,-3,-1,1},{1,-3,6,-10},40] (* _Harvey P. Dale_, Jul 16 2018 *)

%Y Cf. A077990.

%K easy,sign

%O 0,2

%A _Paul Barry_, May 10 2005