Abstract
Given a graphG = (V, E), leta S, S ∈ L, be the edge set incidence vectors of its nontrivial connected subgraphs.
The extreme points ofℬ = {x ∈ R E: asx ≤ |V(S)| - |S|, S ∈ L} are shown to be integer 0/± 1 and characterized. They are the alternating vectorsb k, k ∈ K, ofG.
WhenG is a tree, the extreme points ofB ≥ 0,b kx ≤ 1,k ∈ K} are shown to be the connected vectors ofG together with the origin. For the four LP's associated withℬ andA, good algorithms are given and total dual integrality ofℬ andA proven.
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On leave from Swiss Federal Institute of Technology, Zurich.
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Gröflin, H., Liebling, T.M. Connected and alternating vectors: Polyhedra and algorithms. Mathematical Programming 20, 233–244 (1981). https://doi.org/10.1007/BF01589348
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DOI: https://doi.org/10.1007/BF01589348