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Elementary (-1)-curves of P^3

Antonio Laface·Luca Ugaglia
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Abstract

In this note we deal with rational curves in P^3 which are images of a line by means of a finite sequence of cubo-cubic Cremona transformations. We prove that these curves can always be obtained applying to the line a sequence of such transformations increasing at each step the degree of the curve. As a corollary we get a result about curves that can give speciality for linear systems of P^3.

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Antonio Laface, Luca Ugaglia. 2006-05-03. Elementary (-1)-curves of P^3. https://arxiv.org/abs/math/0605106

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