Triangle-free 2-matchings and M-concave functions on jump systems
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چکیده
منابع مشابه
Triangle-free 2-matchings and M-concave functions on jump systems
For an undirected graph and a fixed integer k, a 2-matching is said to be Ck-free if it has no cycle of length k or less. The problem of finding a maximum cardinality Ck-free 2-matching is polynomially solvable when k ≤ 3, and NP-hard when k ≥ 5. It is known that the polynomial solvability of this problem is closely related to jump systems. Indeed, the degree sequences of the Ck-free 2-matching...
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A 2-matching in an undirected graph G = (V G,EG) is a function x : EG → {0, 1, 2} such that for each node v ∈ V G the sum of values x(e) on all edges e incident to v does not exceed 2. The size of x is the sum ∑ e x(e). If {e ∈ EG | x(e) 6= 0} contains no triangles then x is called triangle-free. Cornuéjols and Pulleyblank devised a combinatorial O(mn)-algorithm that finds a triangle free 2-mat...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2014
ISSN: 0166-218X
DOI: 10.1016/j.dam.2014.05.016