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Pencils of double coverings of curves

Luis Fuentes Garcia
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Abstract

Let X be a smooth curve of genus g. When pi>=3g and d>=pi-2g+1 we show the existence of a double covering gamma:C-->X where C a smooth curve of genus pi with a base-point-free pencil of degree d which is not the pull-back of a pencil on X.

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Luis Fuentes Garcia. 2007-01-17. Pencils of double coverings of curves. https://arxiv.org/abs/math/0701472

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