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On the regularity of varieties having an extremal secant line

Marie-Amélie Bertin
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Abstract

The Castelnuovo-Mumford regularity of varieties of degree r and dimension n in the r-dimensional projective space that have an extremal secant line, is at least d-r+n+1. We classify these varieties and show that their regularity is exactly d-r+n+1, as predicted by the regularity conjecture.

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Marie-Amélie Bertin. 2000-07-12. On the regularity of varieties having an extremal secant line. https://arxiv.org/abs/math/0007074

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