Strongly maximal matchings in infinite weighted graphs
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چکیده
Given an assignment of weights w to the edges of an infinite graph G, a matching M in G is called strongly w-maximal if for any matching N there holds ∑ {w(e) | e ∈ N \ M} ≤ ∑ {w(e) | e ∈ M \ N}. We prove that if w assumes only finitely many values all of which are rational then G has a strongly w-maximal matching. This result is best possible in the sense that if we allow irrational values or infinitely many values then there need not be a strongly w-maximal matching.
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تاریخ انتشار 2008