Nullity and Loop Complementation for Delta-Matroids
نویسندگان
چکیده
منابع مشابه
On Exchange Axioms for Valuated Matroids and Valuated Delta-Matroids
Two further equivalent axioms are given for valuations of a matroid. Let M = (V,B) be a matroid on a finite set V with the family of bases B. For ω : B → R the following three conditions are equivalent: (V1) ∀B,B′ ∈ B, ∀u ∈ B −B′,∃v ∈ B′ −B: ω(B) + ω(B′) ≤ ω(B − u+ v) + ω(B′ + u− v); (V2) ∀B,B′ ∈ B with B 6= B′, ∃u ∈ B −B′,∃v ∈ B′ −B: ω(B) + ω(B′) ≤ ω(B − u+ v) + ω(B′ + u− v); (V3) ∀B,B′ ∈ B, ∀...
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ژورنال
عنوان ژورنال: SIAM Journal on Discrete Mathematics
سال: 2013
ISSN: 0895-4801,1095-7146
DOI: 10.1137/110854692