Ringi Kim

activity

20132020

most citedThe Alon-Tarsi number of subgraphs of a planar graph

5 citations · 7 across the 7 of their papers we have counts for

collaborators

Showing math.COShow all

13 papers · 1 filter

math.CO2020

Decomposing planar graphs into graphs with degree restrictions

Eun-Kyung Cho, Ilkyoo Choi, Ringi Kim +3

Given a graph $G$ , a decomposition of $G$ is a partition of its edges. A graph is $(d, h)$ -decomposable if its edge set can be partitioned into a $d$ -degenerate graph and a graph w…

math.CO2020

The strong clique number of graphs with forbidden cycles

Eun-Kyung Cho, Ilkyoo Choi, Ringi Kim +1

Given a graph $G$ , the strong clique number of $G$ , denoted $ω_{S} (G)$ , is the maximum size of a set $S$ of edges such that every pair of edges in $S$ has distance at most $2$ in the…

math.CO2020★ 1 cited

Generalized list colouring of graphs

Eun-Kyung Cho, Ilkyoo Choi, Yiting Jiang +4

This paper disproves a conjecture of Wang, Wu, Yan and Xie, and answers in negative a question in Dvorak, Pekarek and Sereni. In return, we pose five open problems.

math.CO2019★ 5 cited

The Alon-Tarsi number of subgraphs of a planar graph

Ringi Kim, Seog-Jin Kim, Xuding Zhu

This paper constructs a planar graph $G_{1}$ such that for any subgraph $H$ of $G_{1}$ with maximum degree $Δ (H) \leq 3$ , $G_{1} - E (H)$ is not $3$ -choosable, and a planar graph $G_{2}$ such…

math.CO2019

Largest 2-regular subgraphs in 3-regular graphs

Ilkyoo Choi, Ringi Kim, Alexandr Kostochka +2

For a graph $G$ , let $f_{2} (G)$ denote the largest number of vertices in a $2$ -regular subgraph of $G$ . We determine the minimum of $f_{2} (G)$ over $3$ -regular $n$ -vertex simple graphs…

math.CO2019

Maximum $k$ -sum $n$ -free sets of the 2-dimensional integer lattice

Ilkyoo Choi, Ringi Kim, Boram Park

For a positive integer $n$ , let $[n]$ denote ${1, \dots, n}$ . For a 2-dimensional integer lattice point $b$ and positive integers $k \geq 2$ and $n$ , a \textit{ $k$ -sum $…