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On codimension two subvarieties of P6

Philippe Ellia·Davide Franco
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Abstract

We prove the following: (a) Let X be a smooth, codimension two subvariety of P6. If X lies on a hyperquintic or if deg(X)<74, then X is a complete intersection. (b) Let X be a smooth, subcanonical threefold in P5. If X lies on a hyperquartic, then X is a complete intersection.

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Philippe Ellia, Davide Franco. 1999-09-23. On codimension two subvarieties of P6. https://arxiv.org/abs/math/9909137

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