منابع مشابه
Abstractly Interpreting Argumentation Frameworks for Sharpening Extensions
ly Interpreting Argumentation Frameworks for Sharpening Extensions Ryuta Arisaka and Jérémie Dauphin [email protected], [email protected]
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There are characteristic classes that are the obstructions to the vanishing of the differentials in the Lyndon-Hochischild-Serre spectral sequence of an extension of an integral lattice L by a group G. These characteristic classes exist in the r-th page of the spectral sequence provided differentials di = 0 for all i < r. If L further decomposes into a sum of G-sublattice L = L ⊕ L, we show tha...
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Let G ≤ Sn be a permutation group of degree n with a quotient isomorphic to Ak. We show that if n < (1/2 − o(1))k then the extension splits. Motivated by this result, Guralnick and Liebeck have shown that the conclusion fails to hold if we allow n to be n = 2k(k − 1), establishing a tight quadratic growth rate for the smallest degree of a faithful permutation representation of a non-split exten...
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ژورنال
عنوان ژورنال: Pacific Journal of Mathematics
سال: 1977
ISSN: 0030-8730,0030-8730
DOI: 10.2140/pjm.1977.68.447