Log del Pezzo surfaces with not small fractional indices

Kento Fujita

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arXiv · 1401.0988

Log del Pezzo surfaces with not small fractional indices

Kento Fujita

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Abstract

For a log del Pezzo surface $S$, the fractional index $r(S)\in\mathbb{Q}_{>0}$ is the maximum of $r$ with which $-K_S$ can be written as $r$ times some Cartier divisor. We classify all the log del Pezzo surfaces $S$ with $r(S)\geq 1/2$, after the technique of Nakayama.

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BibTeX RIS

Kento Fujita. 2014-01-06. Log del Pezzo surfaces with not small fractional indices. https://arxiv.org/abs/1401.0988

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