Sagbi Bases in Rings of Multiplicative Invariants

نویسندگان

  • ZINOVY REICHSTEIN
  • Z. REICHSTEIN
چکیده

Let k be a field and G be a finite subgroup of GLn(Z). We show that the ring of multiplicative invariants k[x±1 1 , . . . , x ±1 n ] G has a finite SAGBI basis if and only if G is generated by reflections.

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تاریخ انتشار 2002