Kathryn Haymaker

collaborators

3 papers

math.CO2024

Metrics on permutations with the same descent set

Alexander Diaz-Lopez, Kathryn Haymaker, Colin McGarry +1

Let $S_{n}$ be the symmetric group on the set $[n] := {1, 2, \dots, n}$ . Given a permutation $σ = σ_{1} σ_{2} \dots σ_{n} \in S_{n}$ , we say it has a descent at index $i$ if $σ_{i} > σ_{i + 1}$ . Let $…

math.CO2024

Hypergraphs of girth 5 and 6 and coding theory

Kathryn Haymaker, Michael Tait, Craig Timmons

In this paper, we study the maximum number of edges in an $N$ -vertex $r$ -uniform hypergraph with girth $g$ where $g \in {5, 6}$ . Writing $ex_{r} (N, C_{< g})$ f…

math.CO2024

Metrics on permutations with the same peak set

Alexander Diaz-Lopez, Kathryn Haymaker, Kathryn Keough +2

Let $S_{n}$ be the symmetric group on the set ${1, 2, \dots, n}$ . Given a permutation $σ = σ_{1} σ_{2} \dots σ_{n} \in S_{n}$ , we say it has a peak at index $i$ if $σ_{i - 1} < σ_{i} > σ_{i + 1}$ . Let $…