OFFSET
0,3
LINKS
G. Nebe, E. M. Rains and N. J. A. Sloane, Self-Dual Codes and Invariant Theory, Springer, Berlin, 2006. See Section 7.6.1, especially Eq. (7.6.16), p. 220.
FORMULA
For the Molien series see the Maple code.
MAPLE
f1:= 1 + 4*t^3 + 34*t^4 + 88*t^5 + 237*t^6 + 516*t^7 + 1161*t^8 + 2176*t^9 + 3726*t^10 + 5478*t^11 + 7524*t^12 + 9296*t^13 + 10805*t^14 + 5610 *t^15;
f2:=expand(t^30*subs(t=1/t, f1));
g:= (1-t)*(1-t^2)^4*(1-t^3)^7*(1-t^4)^4;
h:=(f1+f2)/g; # This is the Molien series
series(h, t, 48); # N. J. A. Sloane, Jan 29 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 05 2004
EXTENSIONS
There were errors in the definition (in the order and structure of the group). The Molien series was correct, but to make it easier to check I replaced the formulas with Maple code. Thanks to Georg Fischer and Andrey Zabolotskiy for noticing that something was wrong. - N. J. A. Sloane, Jan 29 2021
STATUS
approved