26 citations · 161 across the 33 of their papers we have counts for
9 papers · 1 filter
Competitively tight graphs
Suh-Ryung Kim, Jung Yeun Lee, Boram Park +1
The competition graph of a digraph is a (simple undirected) graph which has the same vertex set as and has an edge between two distinct vertices and if and only if…
Fat Hoffman graphs with smallest eigenvalue at least
Akihiro Munemasa, Yoshio Sano, Tetsuji Taniguchi
In this paper, we show that all fat Hoffman graphs with smallest eigenvalue at least -1-τ, where τis the golden ratio, can be described by a finite set of fat (-1-τ)-irreducible Ho…
The competition hypergraphs of doubly partial orders
Suh-Ryung Kim, Jung Yeun Lee, Boram Park +1
Since Cho and Kim (2005) showed that the competition graph of a doubly partial order is an interval graph, it has been actively studied whether or not the same phenomenon occurs fo…
On the rank functions of -matroids
Yoshio Sano
The notion of -matroids was introduced by U. Faigle and S. Fujishige in 2009 as a general model for matroids and the greedy algorithm. They gave a characterization of…
The competition number of a generalized line graph is at most two
Boram Park, Yoshio Sano
In 1982, Opsut showed that the competition number of a line graph is at most two and gave a necessary and sufficient condition for the competition number of a line graph being one.…
Holes and a chordal cut in a graph
Suh-Ryung Kim, Jung Yeun Lee, Yoshio Sano
A set of vertices of a graph is called a {\em clique cut} of if the subgraph of induced by is a complete graph and the number of connected components of i…