Exact values of defective Ramsey numbers in graph classes

YE Demirci, T Ekim, J Gimbel, MA Yıldız - Discrete Optimization, 2021 - Elsevier
Given a graph G, a k-sparse j-set is a set of j vertices inducing a subgraph with maximum
degree at most k. A k-dense i-set is a set of i vertices that is k-sparse in the complement of G …

Maximum weight t-sparse set problem on vector-weighted graphs

Y Lin, W Lin - RAIRO-Operations Research, 2023 - rairo-ro.org
Let t be a nonnegative integer and G=(V (G), E (G)) be a graph. For v∈ V (G), let NG (v)={u∈
V (G)\{v}: uv∈ E (G)}. And for S⊆ V (G), we define d S (G; v)=| NG (v)∩ S| for v∈ S and d S …

[HTML][HTML] Small 1-defective Ramsey numbers in perfect graphs

T Ekim, J Gimbel, O Şeker - Discrete Optimization, 2019 - Elsevier
In this paper, we initiate the study of defective Ramsey numbers for the class of perfect
graphs. Let PG be the class of all perfect graphs and R 1 PG (i, j) denote the smallest n such …

Sparse Sets in Triangle-free Graphs

T Ekim, BN Erdem, J Gimbel - arXiv preprint arXiv:2406.03290, 2024 - arxiv.org
A set of vertices is $ k $-sparse if it induces a graph with a maximum degree of at most $ k $.
In this missive, we consider the order of the largest $ k $-sparse set in a triangle-free graph …

[HTML][HTML] Advances on defective parameters in graphs

A Akdemir, T Ekim - Discrete Optimization, 2015 - Elsevier
We consider the generalization of Ramsey numbers to the defective framework using k-
dense and k-sparse sets. We construct the first tableaux for defective Ramsey numbers with …

Defective Ramsey Numbers and Defective Cocolorings in Some Subclasses of Perfect Graphs

YE Demirci, T Ekim, MA Yıldız - Graphs and Combinatorics, 2023 - Springer
In this paper, we investigate a variant of Ramsey numbers called defective Ramsey numbers
where cliques and independent sets are generalized to k-dense and k-sparse sets, both …

On subgraphs without large components

GG Chappell, J Gimbel - Mathematica Bohemica, 2017 - dml.cz
We consider, for a positive integer $ k $, induced subgraphs in which each component has
order at most $ k $. Such a subgraph is said to be $ k $-divided. We show that finding large …

Defective Ramsey numbers in graph classes

YE Demirci, T Ekim, J Gimbel, MA Yıldız - arXiv preprint arXiv:1912.03705, 2019 - arxiv.org
Given a graph $ G $, a $ k $-sparse $ j $-set is a set of $ j $ vertices inducing a subgraph
with maximum degree at most $ k $. A $ k $-dense $ i $-set is a set of $ i $ vertices that is $ k …

DEFECTIVE RAMSEY NUMBERS: CLASSICAL PROOFS AND COMPUTER ENUMERATIONS

T Ekim - gcgt.ug.edu.pl
We investigate a variant of Ramsey numbers called defective Ramsey numbers, introduced
by Ekim and Gimbel in 2013, where cliques and independent sets are generalized to k …

Some of My Favorite Coloring Problems for Graphs and Digraphs

J Gimbel - Graph Theory: Favorite Conjectures and Open …, 2016 - Springer
One of the central notions in graph theory is that of a coloring–a partition of the vertices
where each part induces a graph with some given property. The most studied property is that …