Seunghun Lee

activity

20132026

most citedNerves, minors, and piercing numbers

4 citations · 6 across the 9 of their papers we have counts for

collaborators

Showing math.COShow all

8 papers · 1 filter

math.CO2026

Polytopes with large transversal ratio

Michael Gene Dobbins, Seunghun Lee

The transversal ratio of a polytope $P$ is the minimum proportion of vertices of $P$ required to intersect each facet of $P$ . The weak chromatic number of $P$ is the minimum number…

math.CO2023

On colorings of hypergraphs embeddable in $R^{d}$

Seunghun Lee, Eran Nevo

The (weak) chromatic number of a hypergraph $H$ , denoted by $χ (H)$ , is the smallest number of colors required to color the vertices of $H$ so that no hyperedge of $H$ is monochroma…

math.CO2021

Transversals and colorings of simplicial spheres

Joseph Briggs, Michael Gene Dobbins, Seunghun Lee

Motivated from the surrounding property of a point set in $R^{d}$ introduced by Holmsen, Pach and Tverberg, we consider the transversal number and chromatic number of a simp…

math.CO2020★ 2 cited

Leray numbers of complexes of graphs with bounded matching number

Andreas F. Holmsen, Seunghun Lee

Given a graph $G$ on the vertex set $V$ , the non-matching complex of $G$ , $NM_{k} (G)$ , is the family of subgraphs $G^{'} \subset G$ whose matching number $ν (G^{'})$ is strictly le…

math.CO2019

The sandpile group of a trinity and a canonical definition for the planar Bernardi action

Tamás Kálmán, Seunghun Lee, Lilla Tóthmérész

Baker and Wang define the so-called Bernardi action of the sandpile group of a ribbon graph on the set of its spanning trees. This potentially depends on a fixed vertex of the grap…

math.CO2017

On a conjecture of Karasev

Seunghun Lee, Kangmin Yoo

Karasev conjectured that for any set of $3 k$ lines in general position in the plane, which is partitioned into $3$ color classes of equal size $k$ , the set can be partitioned into…

math.CO2017★ 4 cited

Nerves, minors, and piercing numbers

Andreas F. Holmsen, Minki Kim, Seunghun Lee

We make the first step towards a "nerve theorem" for graphs. Let $G$ be a simple graph and let $F$ be a family of induced subgraphs of $G$ such that the intersection of a…

math.CO2015

Orthogonal colorings of the sphere