Abstract
Let X be a nonsingular complex projective surface and let D be an ample divisor on X such that the associated invertible sheaf is spanned by its global sections. We prove that D is 2-connected apart from a few cases we explicitly describe. We also provide a corresponding result for the 3-connectedness when D2⩾10 and for the 4-connectedness when D2⩾17 and D is very ample.
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Beltrametti, M., Lanteri, A. On the 2 and the 3-connectedness of ample divisors on a surface. Manuscripta Math 58, 109–128 (1987). https://doi.org/10.1007/BF01169086
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DOI: https://doi.org/10.1007/BF01169086