منابع مشابه
Decomposable Ternary Cubics
Cubic forms in three variables are parametrised by points of a projec-tive space P 9. We study the subvarieties in this space defined by de-composable forms. Specifically, we calculate their equivariant minimal resolutions and describe their ideals invariant-theoretically.
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Some geometry and combinatorics for the S-invariant of ternary cubics. Introduction.
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In earlier papers [Wilson 04, Totaro 04], the S-invariant of a ternary cubic f was interpreted in terms of the curvature of related Riemannian and pseudo-Riemannian metrics — this is clarified further in Section 1. In the case when f arises from the cubic form on the second cohomology of a smooth projective threefold with second Betti number three, the value of the S-invariant is closely linked...
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A well-known result of Beukers [3] on the generalized Ramanujan-Nagell equation has, at its heart, a lower bound on the quantity |x2 − 2n|. In this paper, we derive an inequality of the shape |x3 − 2n| ≥ x4/3, valid provided x3 6= 2n and (x, n) 6= (5, 7), and then discuss its implications for a variety of Diophantine problems.
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ژورنال
عنوان ژورنال: Experimental Mathematics
سال: 2002
ISSN: 1058-6458,1944-950X
DOI: 10.1080/10586458.2002.10504469