On the Denominator of the Poincaré Series for Monomial Quotient Rings
نویسندگان
چکیده
Let S = k[x1, . . . , xn] be a polynomial ring over a field k and I a monomial ideal of S. It is well known that the Poincaré series of k over S/I is rational. We describe the coefficients of the denominator of the series and study the multigraded homotopy Lie algebra of S/I.
منابع مشابه
Combinatorics of Multigraded Poincaré Series for Monomial Rings
Backelin proved that the multigraded Poincaré series for resolving a residue field over a polynomial ring modulo a monomial ideal is a rational function. The numerator is simple, but until the recent work of Berglund there was no combinatorial formula for the denominator. Berglund’s formula gives the denominator in terms of ranks of reduced homology groups of lower intervals in a certain lattic...
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