On a special class of simplicial toric varieties
نویسنده
چکیده
We show that for all n ≥ 3 and all primes p there are infinitely many simplicial toric varieties of codimension n in the 2n-dimensional affine space whose minimum number of defining equations is equal to n in characteristic p, and lies between 2n − 2 and 2n in all other characteristics. In particular, these are new examples of varieties which are settheoretic complete intersections only in one positive characteristic. Moreover, we show that the minimum number of binomial equations which define these varieties in all characteristics is 4 for n = 3 and 2n − 2 + (
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