On unimodular rows
نویسندگان
چکیده
منابع مشابه
Suslin's algorithms for reduction of unimodular rows
A well-known lemma of Suslin says that for a commutative ring A if (v1(X), . . . , vn(X)) ∈ (A[X])n is unimodular where v1 is monic and n ≥ 3, then there exist γ1, . . . , γ` ∈ En−1(A[X]) such that the ideal generated by Res(v1, e1.γ1 (v2, . . . , vn)), . . . , Res(v1, e1.γ` (v2, . . . , vn)) equals A. This lemma played a central role in the resolution of Serre’s conjecture. In case A contains ...
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A (0, 1) matrix A is strongly unimodular if A is totally unimodular and every matrix obtained from A by setting a nonzero entry to 0 is also totally unimodular. Here we consider the linear discrepancy of strongly unimodular matrices. It was proved by Lováz, et.al. [5] that for any matrix A, lindisc(A) ≤ herdisc(A). (1) When A is the incidence matrix of a set-system, a stronger inequality holds:...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1985
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1985-0801320-0