Hilbert basis of the Lipman semigroup

Abstract

In this work, we give a new method to compute the Hilbert basis of the semigroup of certain positive divisors supported on the exceptional divisor of a normal surface singularity. Our approach is purely combinatorial which permits to avoid the long calculation of the invariants of the ring as it is presented in the work of Altinok and Tosun.

In Theorem~4, the Cartesian product $S=S_1\times S_2$ is replaced with a fiber product $S=S_1{\times }_{\mathcal{E}}{S}_2$, thanks are due to Zach Teitler for his careful reading

References in corpus (1)

• Lattice cohomology of normal surface singularities