Existence of orbifolds IV: Examples
نویسندگان
چکیده
منابع مشابه
Examples of Type IV unprojection
I show that P(2, 3) has an embedding P(2, 3) ∼= Γ ⊂ P(4, 5, 6, 9) whose image Γ is contained in a quasismooth K3 hypersurface X24 ⊂ P(4, 5, 6, 9). The pair Γ ⊂ X24 unprojects to the codimension 4 K3 surface Y ⊂ P(4, 5, 5, 6, 7, 8, 9) with Basket = [ 1 2 (1, 1), 1 5 (1, 4), 1 5 (2, 3), 1 9 (4, 5) ]. Numerator = 1− t − t − 2t − 2t − 2t − t + t + 2t + 3t + 4t + 3t + · · · (Altınok4(111) in the Mag...
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In [5] Raghavarao showed that if n = 2 (mod 4) and A is a {O, 1, -1} matrix satisfying AAt = (n 1) In. then n 1 = a2 b2 for a, b integers. In [4] van Lint and Seidel giving a proof modeled on a proof of the Witt cancellation theorem, proved more generally that if n is as above and A is a rational matrix satisfying AAt = kIn then k = q12 + q22 (q1, q2 E Q, the rational numbers). Consequently, if...
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ژورنال
عنوان ژورنال: Communications in Algebra
سال: 1996
ISSN: 0092-7872,1532-4125
DOI: 10.1080/00927879608825639