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Molien series for symmetrized weight enumerators of doubly-even Euclidean self-dual codes over the Galois ring GR(4,2).
0

%I #7 Oct 04 2012 10:28:53

%S 1,2,8,32,119,438,1483,4463,12121,30047,68783,147178,297234,570865,

%T 1049605,1857388,3177426,5274519,8523168,13442921,20742950,31376270,

%U 46605818,68084760,97952005,138945430,194536354,269086136,368028405,498081190,667490215,886307575

%N Molien series for symmetrized weight enumerators of doubly-even Euclidean self-dual codes over the Galois ring GR(4,2).

%H G. Nebe, E. M. Rains and N. J. A. Sloane, <a href="http://neilsloane.com/doc/cliff2.html">Self-Dual Codes and Invariant Theory</a>, Springer, Berlin, 2006.

%H <a href="/index/Mo#Molien">Index entries for Molien series</a>

%F G.f.: u1/u2 where u1 := f(t^4), u2 := (1-t^4)^2*(1-t^8)^3*(1-t^12)^3*(1-t^20)^2 and

%F f(t) = 1 + 2*t^2 + 15*t^3 + 51*t^4 + 170*t^5 + 500*t^6 + 1136*t^7 + 2126*t^8 + 3439*t^9 + 4822*t^10 + 5908*t^11 + 6473*t^12 + 6325*t^13 + 5437*t^14 + 4124*t^15 + 2764*t^16 + 1596*t^17 + 764*t^18 + 305*t^19 + 95*t^20 + 20*t^21 + 5*t^22 + 2*t^23.

%K nonn

%O 0,2

%A G. Nebe (nebe(AT)math.rwth-aachen.de), Nov 10, 2004