manuscripta mathematica

, Volume 77, Issue 1, pp 201–213

On the computation of a-invariants

  • Winfried Bruns
  • Jürgen Herzog


Thea-invariant of a graded Cohen-Macaulay ring is the least degree of a generator of its graded canonical module. We compute thea-invariants of (i) graded algebras with straightening laws on upper semi-modular lattices and (ii) the Stanley-Reisner rings of shellable weighted simplicial complexes. The formulas obtained are applied to rings defined by determinantal and pfaffian ideals.


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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • Winfried Bruns
    • 1
    • 2
  • Jürgen Herzog
    • 1
    • 2
  1. 1.Standort VechtaUniversität OsnabrückVechta
  2. 2.FB Mathematik u. InformatikUniversität EssenEssen

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