m at h . A C ] 2 6 A ug 2 00 6 MINIMAL GENERATORS FOR INVARIANT IDEALS
نویسنده
چکیده
Let K be a field, and let R = K[X] be the polynomial ring in an infinite collection X of indeterminates over K. Let S X be the symmetric group of X. The group S X acts naturally on R, and this in turn gives R the structure of a left module over the (left) group ring R[S X ]. A recent theorem of Aschenbrenner and Hillar states that the module R is Noetherian. We prove that submodules of R can have any number of minimal generators.
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