Results 71 to 80 of about 850,474 (224)

On Endomorphism Universality of Sparse Graph Classes

Journal of Graph Theory, Volume 110, Issue 2, Page 223-244, October 2025.
ABSTRACT We show that every commutative idempotent monoid (a.k.a. lattice) is the endomorphism monoid of a subcubic graph. This solves a problem of Babai and Pultr and the degree bound is best‐possible. On the other hand, we show that no class excluding a minor can have all commutative idempotent monoids among its endomorphism monoids. As a by‐product,
Kolja Knauer, Gil Puig i Surroca
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

Frequent Subgraph Mining in Outerplanar Graphs [PDF]

, 2010
In recent years there has been an increased interest in frequent pattern discovery in large databases of graph structured objects. While the frequent connected subgraph mining problem for tree datasets can be solved in incremental polynomial time, it ...
Horvath, Tamas, Ramon, Jan, Wrobel, Stefan   +2 more
core   +1 more source

Minimal Cycle Bases of Outerplanar Graphs [PDF]

The Electronic Journal of Combinatorics, 1998
2-connected outerplanar graphs have a unique minimal cycle basis with length $2\vert E\vert-\vert V\vert$. They are the only Hamiltonian graphs with a cycle basis of this length.
Leydold, Josef, Stadler, Peter F.
openaire   +6 more sources

Tight Distance Query Reconstruction for Trees and Graphs Without Long Induced Cycles

Random Structures &Algorithms, Volume 66, Issue 4, July 2025.
ABSTRACT Given access to the vertex set V$$ V $$ of a connected graph G=(V,E)$$ G=\left(V,E\right) $$ and an oracle that given two vertices u,v∈V$$ u,v\in V $$, returns the shortest path distance between u$$ u $$ and v$$ v $$, how many queries are needed to reconstruct E$$ E $$?
Paul Bastide, Carla Groenland
wiley   +1 more source

Feedback Arc Number and Feedback Vertex Number of Cartesian Product of Directed Cycles

Discrete Dynamics in Nature and Society, Volume 2019, Issue 1, 2019., 2019
For a digraph D, the feedback vertex number τ(D), (resp. the feedback arc number τ′(D)) is the minimum number of vertices, (resp. arcs) whose removal leaves the resultant digraph free of directed cycles. In this note, we determine τ(D) and τ′(D) for the Cartesian product of directed cycles D=Cn1→□Cn2→□…Cnk→. Actually, it is shown that τ′D=n1n2…nk∑i=1k1/
Xiaohong Chen, Baoyindureng Wu, Seenith Sivasundaram   +2 more
wiley   +1 more source

On the Relationships between Zero Forcing Numbers and Certain Graph Coverings

Special Matrices, 2014
The zero forcing number and the positive zero forcing number of a graph are two graph parameters that arise from two types of graph colourings. The zero forcing number is an upper bound on the minimum number of induced paths in the graph that cover all ...
Taklimi Fatemeh Alinaghipour, Fallat Shaun, Meagher Karen   +2 more
doaj   +1 more source

On vertex‐transitive graphs with a unique hamiltonian cycle

Journal of Graph Theory, Volume 108, Issue 1, Page 65-99, January 2025.
Abstract A graph is said to be uniquely hamiltonian if it has a unique hamiltonian cycle. For a natural extension of this concept to infinite graphs, we find all uniquely hamiltonian vertex‐transitive graphs with finitely many ends, and also discuss some examples with infinitely many ends.
Babak Miraftab, Dave Witte Morris
wiley   +1 more source

Vertex Colorings without Rainbow Subgraphs

Discussiones Mathematicae Graph Theory, 2016
Given a coloring of the vertices of a graph G, we say a subgraph is rainbow if its vertices receive distinct colors. For a graph F, we define the F-upper chromatic number of G as the maximum number of colors that can be used to color the vertices of G ...
Goddard Wayne, Xu Honghai
doaj   +1 more source

Outerplanar Partitions of Planar Graphs

Journal of Combinatorial Theory, Series B, 1996
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +3 more sources