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A092201
Molien series for 16-dimensional group of structure O_{4}^{+}(2) and order 72, corresponding to genus 2 complete weight enumerators of Hermitian self-dual GF(2)-linear codes over GF(4).
1
1, 3, 11, 38, 127, 396, 1179, 3297, 8746, 22002, 52730, 120770, 265416, 561440, 1146924, 2268970, 4358413, 8147638, 14854450, 26461264, 46135068, 78845138, 132262964, 218050742, 353688548, 565028243, 889832807, 1382620648, 2121243721, 3215727006
OFFSET
0,2
LINKS
G. Nebe, E. M. Rains and N. J. A. Sloane, Self-Dual Codes and Invariant Theory, Springer, Berlin, 2006.
FORMULA
G.f.: u1/u2, where u1 := f0 + x^30*subs(x=x^(-1), f0); f0 := 1 + 10*x^3 + 25*x^4 + 53*x^5 + 121*x^6 + 247*x^7 + 471*x^8 + 803*x^9 + 1201*x^10 + 1674*x^11 + 2182*x^12 + 2616*x^13 + 2911*x^14 + 1509*x^15; u2 := (1-x)^3*(1-x^2)^5*(1-x^3)^3*(1-x^4)^3*(1-x^6)^2.
CROSSREFS
Cf. A092203.
Sequence in context: A129962 A026361 A006189 * A273526 A026943 A307571
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 02 2004
STATUS
approved