Some calculations on type II1 unprojection
نویسنده
چکیده
The type II1 unprojection is, by definition, the generic complete intersection type II unprojection, in the sense of [P] Section 3.1, for the parameter value k = 1, and depends on a parameter n ≥ 2. Our main results are the explicit calculation of the linear relations of the type II1 unprojection for any value n ≥ 2 (Theorem 3.16) and the explicit calculation of the quadratic equation for the case n = 3 (Theorem 4.1). In addition, Section 5 contains applications to algebraic geometry, while Section 6 contains the Macaulay 2 code for the type II1 unprojection for the parameter value n = 3.
منابع مشابه
The equations of type II1 unprojection
The type II1 unprojection is, by definition, the generic complete intersection type II unprojection, in the sense of [P] Section 3.1, for the parameter value k = 1, and depends on a parameter n ≥ 2. Our main results are the explicit calculation of the linear relations of the type II1 unprojection for any value n ≥ 2 (Theorem 3.16) and the explicit calculation of the quadratic equation for the c...
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