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%I #11 Dec 29 2023 19:01:05
%S 1,0,-1,0,0,-1,0,2,1,-1,-1,-1,-1,0,2,4,2,-4,-6,-2,0,2,10,11,-4,-17,
%T -14,-4,7,22,30,11,-31,-57,-35,15,56,80,64,-32,-152,-160,-28,136,240,
%U 228,29,-312,-521,-324,208,691,784,358,-523,-1401,-1417,-149,1631,2560,1826,-492,-3366,-4692
%N Expansion of 1/(x^11 + x^10 + x^6 + x^5 + x^4 + x^2 + 1).
%D J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. xxxiii.
%H <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (0, -1, 0, -1, -1, -1, 0, 0, 0, -1, -1).
%F G.f.: 1/(x^11 + x^10 + x^6 + x^5 + x^4 + x^2 + 1).
%F a(n) + a(n-2) + a(n-4) + a(n-5) + a(n-6) + a(n-10) + a(n-11) = 0. - _Wesley Ivan Hurt_, Dec 29 2023
%t f[x_] = 1 + x + x^5 + x^6 + x^7 + x^9 + x^11;
%t g[x] = ExpandAll[x^11*f[1/x]];
%t a = Table[SeriesCoefficient[ Series[1/g[x], {x, 0, 50}], n], {n, 0, 50}]
%K sign,easy
%O 0,8
%A _Roger L. Bagula_, Mar 05 2009
%E New name, _Joerg Arndt_, Mar 20 2013