%I A157746
%S A157746 1,0,1,0,0,1,0,2,1,1,1,1,1,0,2,4,2,4,6,2,0,2,10,11,4,17,14,
%T A157746 4,7,22,30,11,31,57,35,15,56,80,64,32,152,160,28,136,240,228,29,
%U A157746 312,521,324,208
%V A157746 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,-14,
%W A157746 -4,7,22,30,11,-31,-57,-35,15,56,80,64,-32,-152,-160,-28,136,240,228,29,
%X A157746 -312,-521,-324,208
%N A157746 An expansion of polynomial Golay polynomial: g_2(x)=1 + x + x^5 + x^6 
               + x^7 + x^9 + x^11; f(x)=1/(g_2(1/x)*x^11)=1 + x^2 + x^4 + x^5 + 
               x^6 + x^10 + x^11.
%C A157746 Characteristic matrix of of the toral inverse polynomial is:
%C A157746 {{0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0},
%C A157746 {0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0},
%C A157746 {0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0},
%C A157746 {0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0},
%C A157746 {0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0},
%C A157746 {0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0},
%C A157746 {0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0},
%C A157746 {0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0},
%C A157746 {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0},
%C A157746 {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
%C A157746 {-1, 0, -1, 0, -1, -1, -1, 0, 0, 0, -1}}
%D A157746 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", 
               Springer-Verlag, p. xxxiii.
%F A157746 g_2(x)=1 + x + x^5 + x^6 + x^7 + x^9 + x^11;
%F A157746 f(x)=1/(g_2(1/x)*x^11)=1 + x^2 + x^4 + x^5 + x^6 + x^10 + x^11;
%F A157746 a(n)=coefficients(f(x))
%t A157746 f[x_] = 1 + x + x^5 + x^6 + x^7 + x^9 + x^11;
%t A157746 g[x] = ExpandAll[x^11*f[1/x]];
%t A157746 a = Table[SeriesCoefficient[ Series[1/g[x], {x, 0, 50}], n], {n, 0, 50}]
%Y A157746 Sequence in context: A079635 A037909 A000164 this_sequence A037820 A076493 
               A037910
%Y A157746 Adjacent sequences: A157743 A157744 A157745 this_sequence A157747 A157748 
               A157749
%K A157746 sign,uned
%O A157746 0,8
%A A157746 Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Mar 05 2009