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Expansion of Molien series for the ring of genus 5 code polynomials for Type II codes.
1

%I #20 Mar 25 2017 10:09:58

%S 1,0,1,0,2,2,8,8,34,60,203,553,2063,7359,30811,127416,541644,2235677,

%T 8966371,34413747,126465849,443858877,1490702752,4796609651,

%U 14821521743,44071296447,126388352322,350298687803,940211047828

%N Expansion of Molien series for the ring of genus 5 code polynomials for Type II codes.

%H Ray Chandler, <a href="/A144060/b144060.txt">Table of n, a(n) for n = 0..2000</a>

%H Ray Chandler, <a href="/A144060/a144060.txt">Mathematica program</a>

%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 M. Oura, <a href="http://projecteuclid.org/euclid.ojm/1200787332">The dimension formula for the ring of code polynomials in genus 4</a>, Osaka J. Math. 34 (1997), 53-72.

%H M. Oura, <a href="http://web.archive.org/web/20070102035724/http://www.math.kochi-u.ac.jp/oura/molienH5">The dimension formula of the invariant ring of H5</a> (web archive).

%H <a href="/index/Rec#order_532">Index entries for linear recurrences with constant coefficients</a>, order 532.

%F Oura (see link) gives the Molien series explicitly.

%e 1 + x^8 + 2*x^16 + 2*x^20 + 8*x^24 + 8*x^28 + 34*x^32 + 60*x^36 + 203*x^40 + 553*x^44 + 2063*x^48 + 7359*x^52 + 30811*x^56 + 127416*x^60 + 541644*x^64 + 2235677*x^68 + 8966371*x^72 + 34413747*x^76 + 126465849*x^80 + 443858877*x^84 + 1490702752*x^88 + 4796609651*x^92 + 14821521743*x^96 + .....

%t See link for Mathematica program.

%Y Cf. A027672, A051354.

%K nonn

%O 0,5

%A _N. J. A. Sloane_, Dec 22 2008, following a suggestion from G. Nebe.

%E More terms from _Ray Chandler_, Mar 23 2017