Results 81 to 90 of about 4,621 (198)
Strong Oriented Chromatic Number of Planar Graphs without Short Cycles [PDF]
Let M be an additive abelian group. An M-strong-oriented coloring of an oriented graph G is a mapping f from V(G) to M such that f(u) j(v) whenever uv is an arc in G and f(v)−f(u) −(f(t)−f(z)) whenever uv and zt are two arcs in G.
Mickael Montassier +2 more
doaj +1 more source
On edge-group choosability of graphs [PDF]
In this paper, we study the concept of edge-group choosability of graphs. We say that G is edge k-group choosable if its line graph is k-group choosable. An edge-group choosability version of Vizing conjecture is given.
Khamseh, Amir, Omidi, Gholamreza
core
Outerplanar Partitions of Planar Graphs
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire +2 more sources
The product structure of squaregraphs
Abstract A squaregraph is a plane graph in which each internal face is a 4‐cycle and each internal vertex has degree at least 4. This paper proves that every squaregraph is isomorphic to a subgraph of the semistrong product of an outerplanar graph and a path.
Robert Hickingbotham +3 more
wiley +1 more source
Small Superpatterns for Dominance Drawing
We exploit the connection between dominance drawings of directed acyclic graphs and permutations, in both directions, to provide improved bounds on the size of universal point sets for certain types of dominance drawing and on superpatterns for certain ...
Bannister, Michael J. +2 more
core +1 more source
On Vertices Enforcing a Hamiltonian Cycle
A nonempty vertex set X ⊆ V (G) of a hamiltonian graph G is called an H-force set of G if every X-cycle of G (i.e. a cycle of G containing all vertices of X) is hamiltonian.
Fabrici Igor +2 more
doaj +1 more source
To Prove Four Color Theorem [PDF]
In this paper, we give a proof for four color theorem(four color conjecture). Our proof does not involve computer assistance and the most important is that it can be generalized to prove Hadwiger Conjecture. Moreover, we give algorithms to color and test
Cao, Weiwei, Yue, Weiya
core
A generalization of outerplanar graphs [PDF]
A planar graph is said to be a generalized outerplanar graph if it has an embedding in the plane in which every edge is incident to a vertex laying on the boundary of the outer face. The author presents a characterization of generalized outerplanar graphs by means of a set of exactly 12 forbidden subgraphs (up to homeomorphism).
openaire +1 more source
We propose aggregative context-aware fitness functions based on feature selection for evolutionary learning of characteristic graph patterns. The proposed fitness functions estimate the fitness of a set of correlated individuals rather than the sum of ...
Fumiya Tokuhara +4 more
doaj +1 more source
An O(mn2) Algorithm for Computing the Strong Geodetic Number in Outerplanar Graphs
Let G = (V (G), E(G)) be a graph and S be a subset of vertices of G. Let us denote by γ[u, v] a geodesic between u and v. Let Γ(S) = {γ[vi, vj] | vi, vj ∈ S} be a set of exactly |S|(|S|−1)/2 geodesics, one for each pair of distinct vertices in S.
Mezzini Mauro
doaj +1 more source

