manuscripta mathematica

, Volume 59, Issue 3, pp 347–374 | Cite as

The semigroup of values of a curve singularity with several branches

  • Félix Delgado de la Mata


We give an explicit description of the semigroup of values of a plane curve singularity with several branches in terms of the usual invariants of the equisingularity type in the sense of Zariski. The main tool is the set of elements called maximals, specially the absolute and the relative ones. First, we describe the semigroup in terms of the relative maximals and these ones in terms of the absolute maximals by means of a symmetry property which generalizes the well known property of symmetry for the singularities with only one branch. Then the absolute maximals are described in terms of the theory of maximal contact of higher genus developed by Lejeune.


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Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • Félix Delgado de la Mata
    • 1
  1. 1.Dpto. Algebra y Geometría Facultad de CienciasUniversidad de ValladolidValladolidSpain

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