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%I #11 Feb 26 2018 17:00:03
%S 1,7,44,262,1504,8416,46208,250016,1337088,7083264,37229568,194383360,
%T 1009172480,5213634560,26819756032,137445318656,702021435392,
%U 3574958587904,18156130926592,91985567678464,465004476235776,2345955741401088,11813573860786176
%N a(n) = (1/8)*A291387(n).
%H Clark Kimberling, <a href="/A291388/b291388.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (8,-8,-32,-16)
%F G.f.: -(((1 + x) (-1 + 2 x + 2 x^2))/(-1 + 4 x + 4 x^2)^2).
%F a(n) = 8*a(n-1) - 8*a(n-2) - 32*a(n-3) - 16*a(n-4) for n >= 5.
%t z = 60; s = x + x^2; p = (1 - 4 s)^2;
%t Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A019590 *)
%t u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A291387 *)
%t u / 8 (* A291388 *)
%o (GAP)
%o a:=8*[1,7,44,262];; for n in [5..10^2] do a[n]:=8*a[n-1]+-8*a[n-2]-32*a[n-3]-16*a[n-4]; od;
%o A291388:=(1/8)*a; # _Muniru A Asiru_, Sep 07 2017
%Y Cf. A019590, A291382, A291388.
%K nonn,easy
%O 0,2
%A _Clark Kimberling_, Sep 04 2017
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