136 search results - page 1 / 28 » Graph parameters and semigroup functions |
EJC
2008
13 years 4 months ago
2008
Abstract. We prove a general theorem on semigroup functions that implies characterizations of graph partition functions in terms of the positive semidefiniteness (`reflection posit...
COMBINATORICS
2007
13 years 4 months ago
2007
We introduce and develop a two-parameter chromatic symmetric function for a simple graph G over the field of rational functions in q and t , Q (q, t). We derive its expansion in ...
LATIN
2004
Springer
13 years 10 months ago
2004
Springer
For several graph-theoretic parameters such as vertex cover and dominating set, it is known that if their sizes are bounded by k then the treewidth of the graph is bounded by some ...
ICALP
2003
Springer
13 years 9 months ago
2003
Springer
The (k, r)-center problem asks whether an input graph G has ≤ k vertices (called centers) such that every vertex of G is within distance ≤ r from some center. In this paper we ...
STACS
2009
Springer
13 years 11 months ago
2009
Springer
The notions of hypertree width and generalized hypertree width were introduced by Gottlob, Leone, and Scarcello in order to extend the concept of hypergraph acyclicity. These noti...