6 papers · 1 filter
Short Rainbow Circuits in Regular Matroids
Sean McGuinness
DeVos et al conjectured that if is a simple, regular matroid and is a colouring of the elements of with colours, where each colour class has at least two eleme…
Skew circuits and circumference in a binary matroid
Sean McGuinness
Let C_1 and C_2 be skew circuits in a binary matroid having circumference c. For any positive integer k there is a constant a_k such that if min { |A| ; C_1 \subset A \subset E-A}…
Cyclic Orderings of Paving Matroids
Sean McGuinness
A matroid M is cyclically orderable if there is a cyclic permutation of the elements of M such that any r consecutive elements form a basis in M. An old conjecture of Kajitani, Miy…
Serial Exchanges in Random Bases
Sean McGuinness
It was conjectured by Kotlar and Ziv that for any two bases and in a matroid and any subset , there is a subset and orderings $x_1 \prec x_2 \pre…
Frame Matroids, Toric Ideals, and a Conjecture of White
Sean McGuinness
Blasiak verified a conjecture of White for graphic matroids by showing that the toric ideal of a graphic matroid is generated by quadrics. In this paper, we extend this result to f…
Girth conditions and Rota's basis conjecture
Benjamin Friedman, Sean McGuinness
Rota's basis conjecture (RBC) states that given a collection of bases in a matroid of rank , one can always find disjoint rainbow bases with respect to…