Zach Walsh

collaborators

3 papers

math.CO2025

The column number for 3-modular matrices

Joseph Paat, Zach Walsh, Luze Xu

An integer-valued matrix $A$ is $Δ$ -modular if each $rank (A) \times rank (A)$ submatrix has determinant at most $Δ$ in absolute value. The c…

math.OC2023

Extended formulations for the integer hull of strictly $Δ$ -modular cographic polyhedral cones

Joseph Paat, Zach Walsh, Luze Xu

Conforti et al. give a compact extended formulation for a class of bimodular-constrained integer programs, namely those that model the stable set polytope of a graph with no disjoi…

math.CO2023

Dense circuit graphs and the planar Turán number of a cycle

Ruilin Shi, Zach Walsh, Xingxing Yu

The $planar Tur a ˊ n number$ $ex_{P} (n, H)$ of a graph $H$ is the maximum number of edges in an $n$ -vertex planar graph without $H$ as a subgraph. Let $C_{k}$ …

The column number for 3-modular matrices

Extended formulations for the integer hull of strictly Δ-modular cographic polyhedral cones

Dense circuit graphs and the planar Turán number of a cycle

Extended formulations for the integer hull of strictly $Δ$ -modular cographic polyhedral cones