[HTML][HTML] Computing square roots of trivially perfect and threshold graphs

M Milanič, O Schaudt - Discrete Applied Mathematics, 2013 - Elsevier
A graph H is a square root of a graph G if two vertices are adjacent in G if and only if they are
at distance one or two in H. Computing a square root of a given graph is NP-hard, even …

[HTML][HTML] Dimension-2 poset competition numbers and dimension-2 poset double competition numbers

Y Wu, J Lu - Discrete Applied Mathematics, 2010 - Elsevier
Let D=(V (D), A (D)) be a digraph. The competition graph of D, is the graph with vertex set V
(D) and edge set {uv∈ V (D) 2:∃ w∈ V (D), uw⃗, vw⃗∈ A (D)}. The double competition …

[HTML][HTML] Edge-clique covers of the tensor product

WK Hon, T Kloks, HH Liu, YL Wang - Theoretical Computer Science, 2015 - Elsevier
In this paper we study the edge-clique cover number, θ e (⋅), of the tensor product K n× K n.
We derive an easy lowerbound for the edge-clique number of graphs in general. We prove …

[HTML][HTML] Unique intersectability of diamond-free graphs

JL Guo, TM Wang, YL Wang - Discrete applied mathematics, 2011 - Elsevier
For a graph G with vertices v1, v2,…, vn, a simple set representation of G is a family F={S1,
S2,…, Sn} of distinct nonempty sets such that| Si∩ Sj|= 1 if vivj is an edge in G, and| Si∩ …

On edge-independent sets

T Kloks, CH Liu, SH Poon - … in Algorithmics and Algorithmic Aspects in …, 2013 - Springer
A set of edges in a graph G is independent if no two elements are contained in a clique of G.
The edge-independent set problem asks for the maximal cardinality of independent sets of …

Set Representations of Linegraphs

JL Guo, TM Wang, YL Wang, T Kloks - arXiv preprint arXiv:1309.0170, 2013 - arxiv.org
Let $ G $ be a graph with vertex set $ V (G) $ and edge set $ E (G) $. A family $\mathcal {S}
$ of nonempty sets $\{S_1,\ldots, S_n\} $ is a set representation of $ G $ if there exists a one …

Independent sets in edge-clique graphs II

CH Liu, T Kloks, SH Poon - arXiv preprint arXiv:1206.5082, 2012 - arxiv.org
We show that edge-clique graphs of cocktail party graphs have unbounded rankwidth. This,
and other observations lead us to conjecture that the edge-clique cover problem is NP …

[HTML][HTML] Recognizing edge clique graphs among interval graphs and probe interval graphs

J Kong, Y Wu - Applied mathematics letters, 2007 - Elsevier
The edge clique graph of a graph H is the one having the edge set of H as vertex set, two
vertices being adjacent if and only if the corresponding edges belong to a common complete …

[PDF][PDF] Weakly clique irreducibility of NEPS of two graphs

A Lakshmanan, A Vijayakumar, TM Wang - 2010 - researchgate.net
A clique of a graph G is essential if it has an edge which does not belong to any other clique
in G. A graph G is weakly clique irreducible if every edge in G belongs to at least one …

Çizgelerin Sperner sayıları

G Başer - 2009 - acikbilim.yok.gov.tr
Dört bölümden olu¸ san bu tezde Çizgelerin Sperner say¬ lar¬ tan¬ t¬ lm¬¸ s ve incelenmi¸
stir. Bu çal¬¸ smaya gerekli olan baz¬ temel Çizgeler teorisi ile ilgili tan¬ mlarla giri¸ s yap¬ …