The cocycle lattice of binary matroids , II
نویسنده
چکیده
We continue the study initiated in [LS] of the lattice (grid) generated by the incidence vectors of cocycles of a binary matroid and its dual lattice. In [LS], we proved that every denominator in the dual lattice is a power of 2, and characterized those binary matroids M for which the largest exponent k(M) is 1. In this paper, we characterize the matroids with k(M) = 2 and, for each constant k, give a polynomial time algorithm to decide whether k(M) ≥ k.
منابع مشابه
The Cocycle Lattice of Binary Matroids
We study the lattice (grid) generated by the incidence vectors of cocycles of a binary matroid and its dual lattice. We characterize those binary matroids for which the obvious necessary conditions for a vector to belong to the cocycle lattice are also sufficient. This characterization yields a polynomial time algorithm to check whether a matroid has this property, and also to construct a basis...
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