Results 41 to 50 of about 584,165 (157)

Simultaneous coloring of vertices and incidences of outerplanar graphs

Electronic Journal of Graph Theory and Applications, 2023
A vi-simultaneous proper k-coloring of a graph G is a coloring of all vertices and incidences of the graph in which any two adjacent or incident elements in the set V(G)∪I(G) receive distinct colors, where I(G) is the set of incidences of G.
Mahsa Mozafari-Nia, Moharram N. Iradmusa
doaj   +1 more source

Toric ideals of matching polytopes and edge colorings

Mathematika, Volume 72, Issue 2, April 2026.
Abstract In this paper, we investigate the maximal degree of minimal generators of the toric ideal of the matching polytope of a graph. It is known that the toric ideal associated with a bipartite graph is generated by binomials of degree at most 3.
Kenta Mori, Ryo Motomura, Hidefumi Ohsugi, Akiyoshi Tsuchiya   +3 more
wiley   +1 more source

Dichotomy Theorems for Homomorphism Polynomials of Graph Classes

Journal of Graph Algorithms and Applications, 2016
In this paper, we will show dichotomy theorems for the computation of polynomials corresponding to evaluation of graph homomorphisms in Valiant's model. We are given a fixed graph H and want to find all graphs, from some graph class, homomorphic
Christian Engels
doaj   +1 more source

Perfect Matching Under Precedence Constraints

Networks, Volume 87, Issue 2, Page 175-190, March 2026.
ABSTRACT In this article, we motivate and define variants of perfect matching under precedence constraints where a perfect matching is built incrementally and precedence constraints ensure that an edge may only be added to the matching if the edge's predecessor vertices have already been covered.
Christina Büsing, Corinna Mathwieser
wiley   +1 more source

Fuzzy Outerplanar Graphs and Its Applications

International Journal of Computational Intelligence Systems
The concept of a crisp graph is essential in the study of outerplanar graphs because outerplanar graphs are a unique type of planar graphs containing special characteristics. One of the core concepts of crisp graphs, the notion of a subgraph, is utilized
Deivanai Jaisankar, Sujatha Ramalingam, Nagarajan Deivanayagampillai, Tadesse Walelign   +3 more
doaj   +1 more source

Straight-Line Drawings on Restricted Integer Grids in Two and Three Dimensions

Journal of Graph Algorithms and Applications, 2003
This paper investigates the following question: Given a grid ϕ, where ϕ is a proper subset of the integer 2D or 3D grid, which graphs admit straight-line crossing-free drawings with vertices located at (integral) grid points of ϕ?
Stefan Felsner, Giuseppe Liotta, Stephen Wismath   +2 more
doaj   +1 more source

Face Sizes and the Connectivity of the Dual

Journal of Graph Theory, Volume 110, Issue 4, Page 379-391, December 2025.
ABSTRACT For each c ≥ 1, we prove tight lower bounds on face sizes that must be present to allow 1‐ or 2‐cuts in simple duals of c‐connected maps. Using these bounds, we determine the smallest genus on which a c‐connected map can have a simple dual with a 2‐cut and give lower and some upper bounds for the smallest genus on which a c‐connected map can ...
Gunnar Brinkmann, Kenta Noguchi, Heidi Van den Camp   +2 more
wiley   +1 more source

Proximity Drawings of Outerplanar Graphs (extended abstract)

, 1997
A proximity drawing of a graph is one in which pairs of adjacent vertices are drawn relatively close together according to some proximity measure while pairs of non-adjacent vertices are drawn relatively far apart.
Lenhart, William J., Liotta, Giuseppe, Giuseppe Liotta, William Lenhart   +3 more
core   +1 more source

Recognizing Trees From Incomplete Decks

Journal of Graph Theory, Volume 110, Issue 3, Page 322-336, November 2025.
ABSTRACT Given a graph G, the unlabeled subgraphs G − v are called the cards of G. The deck of G is the multiset { G − v : v ∈ V ( G ) }. Wendy Myrvold showed that a disconnected graph and a connected graph both on n vertices have at most ⌊ n 2 ⌋ + 1 cards in common and found (infinite) families of trees and disconnected forests for which this upper ...
Gabriëlle Zwaneveld
wiley   +1 more source

On the Edge-length Ratio of Outerplanar Graphs [PDF]

, 2017
International audienceWe show that any outerplanar graph admits a planar straight-line drawing such that the length ratio of the longest to the shortest edges is strictly less than $2$. This result is tight in the sense that for any $\epsilon > 0$ there
Lazard, Sylvain, Lenhart, William, Lenhart, Wiliam J., Liotta, Giuseppe, Giuseppe Liotta, Sylvain Lazard, William J. Lenhart, William Lenhart   +7 more
core   +1 more source