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Expansion of (1-x)^2/((1-x)^3-4x^4).
0

%I #6 Jun 13 2015 00:51:29

%S 1,1,1,1,5,17,41,81,157,337,785,1825,4085,8913,19449,42993,95885,

%T 213777,474465,1049921,2323685,5150865,11429321,25358737,56233853,

%U 124658129,276348849,612740961,1358769877,3013068113,6681031065,14813622577

%N Expansion of (1-x)^2/((1-x)^3-4x^4).

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1,4).

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

%K easy,nonn

%O 0,5

%A _Paul Barry_, Jul 25 2004