Ilkyoo Choi

activity

20142020

most cited

(1, k)

-coloring of graphs with girth at least

5

on a surface

2 citations · 3 across the 5 of their papers we have counts for

collaborators

5 papers

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.CO2020

A sharp Ore-type condition for a connected graph with no induced star to have a Hamiltonian path

Ilkyoo Choi, Jinha Kim

We say a graph $G$ has a Hamiltonian path if it has a path containing all vertices of $G$ . For a graph $G$ , let $σ_{2} (G)$ denote the minimum degree sum of two nonadjacent vertices o…

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 $…

math.CO2014★ 2 cited

$(1, k)$ -coloring of graphs with girth at least $5$ on a surface

Hojin Choi, Ilkyoo Choi, Jisu Jeong +1

A graph is $(d_{1}, ..., d_{r})$ -colorable if its vertex set can be partitioned into $r$ sets $V_{1}, ..., V_{r}$ so that the maximum degree of the graph induced by $V_{i}$ is at most $d_{i}$ …

Generalized list colouring of graphs

A sharp Ore-type condition for a connected graph with no induced star to have a Hamiltonian path

Largest 2-regular subgraphs in 3-regular graphs

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

(1,k)-coloring of graphs with girth at least 5 on a surface

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

$(1, k)$ -coloring of graphs with girth at least $5$ on a surface