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math.CO2025
A new minor-closed class of transversal matroids
Gerry Toft
We provide a characterisation of when a single-element contraction of a transversal matroid is itself transversal. Using this characterisation, we define a new class of transversal…
math.CO2025
The excluded minors of the class of spike minors
Sam Bastida, Nick Brettell, Rutger Campbell +4
Mayhew et al.\ (2021) posed the problem of showing that the minor-closed class of spikes and their minors has a finite set of excluded minors and describing all of them. In this pa…