activity
20232026
most citedChordal matroids arising from generalized parallel connections

1 citations · 1 across the 5 of their papers we have counts for

collaborators

7 papers

math.CO2026

Weighted coloop splittings in rank six

James Dylan Douthitt, Lee Kennard, Josef Komissar

With a view toward applications in Riemannian geometry, we explore coloop splitting properties of regular matroids. Nienhaus showed by classification in rank four that a regular ma…

math.CO2026

Degeneracy: From Graphs to Matroids

Allan Bickle, James Dylan Douthitt, Wayne Ge +1

A graph is -degenerate if every subgraph has a vertex of degree at most . We extend this notion to matroids, defining a loopless matroid to be -degenerate if every res…

math.CO2026

Higher cosystoles of matroids

James Dylan Douthitt, Elana Israel, Lee Kennard

We define a matroid invariant called the three-cosystole that is related to higher notions of cogirth for weighted matroids, and we prove an optimal upper bound for it in the class…

math.CO2025

Rainbow triangles and the Erdős-Hajnal problem in projective geometries

Carolyn Chun, James Dylan Douthitt, Wayne Ge +3

We formulate a geometric version of the Erdős-Hajnal conjecture that applies to finite projective geometries rather than graphs, in both its usual 'induced' form and the multicolou…

math.CO2024

Classes of binary matroids with small lists of excluded induced minors

James Dylan Douthitt, James Oxley

In earlier work, we characterized the class of matroids with no as an induced minor and the class of matroids with no member of as an induced minor. In…

math.CO2024

Chordal matroids arising from generalized parallel connections II

James Dylan Douthitt, James Oxley

In 1961, Dirac showed that chordal graphs are exactly the graphs that can be constructed from complete graphs by a sequence of clique-sums. In an earlier paper, by analogy with Dir…

math.CO2023★ 1 cited

Chordal matroids arising from generalized parallel connections

James Dylan Douthitt, James Oxley

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 repeate…