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(joint work with Bram Broer, Peter Webb and Larry Smith)
The theorem in the title tells us, under certain hypotheses, how to
get a very useful _graded_ version of the (ungraded) coset
representation G/H for a finite group G of GL_n(k) and a subgroup H.
Specifically, you take the polynomials in k[x_1,...,x_n] invariant
under H, and mod out by the ideal generated by the positive degree
polynomials invariant under G.
The problem is that the hypotheses on the group G and the field k are
quite restrictive: one needs for the G-invariants to be a polynomial
algebra, and for |G| to be invertible in k.
So I'll tell you how to get rid of those annoying hypotheses, that is,
how the statement changes without them.
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