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On the analytical invariance of the semigroups of a quasi-ordinary hypersurface singularity

Patrick Popescu-Pampu
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Abstract

We associate to any irreducible germ S of complex quasi-ordinary hypersurface an analytically invariant semigroup. We deduce a direct proof (without passing through their embedded topological invariance) of the analytical invariance of the normalized characteristic exponents. These exponents generalize the generic Newton-Puiseux exponents of plane curves. Incidentally, we give a toric description of the normalization morphism of the germ S.

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Patrick Popescu-Pampu. 2003-05-27. On the analytical invariance of the semigroups of a quasi-ordinary hypersurface singularity. https://arxiv.org/abs/math/0305382

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