The Structure of Delta-Matroids with Width One Twists

Carolyn Chun, Rhiannon Hall, Criel Merino, Iain Moffatt, Steven D Noble

Abstract


The width of a delta-matroid is the difference in size between a maximal and minimal feasible set. We give a Rough Structure Theorem for delta-matroids that admit a twist of width one. We apply this theorem to give an excluded minor characterisation of delta-matroids that admit a twist of width at most one.


Keywords


Delta-matroid; Matroid; Partial dual; Excluded minor; Twist; Width

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