Chordal matroids arising from generalized parallel connections
Abstract
A graph is chordal if every cycle of length at least four has a chord. In 1961, Dirac characterized chordal graphs as those graphs that can be built from complete graphs by repeated clique-sums. Generalizing this, we consider the class of simple $GF(q)$-representable matroids that can be built from projective geometries over $GF(q)$ by repeated generalized parallel connections across projective geometries. We show that this class of matroids is closed under induced minors. We characterize the class by its forbidden induced minors; the case when $q=2$ is distinctive.
- Publication:
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arXiv e-prints
- Pub Date:
- June 2023
- DOI:
- arXiv:
- arXiv:2306.07514
- Bibcode:
- 2023arXiv230607514D
- Keywords:
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- Mathematics - Combinatorics
- E-Print:
- doi:10.1016/j.aam.2023.102631