Примеры использования Maximal planar graphs на Английском языке и их переводы на Русский язык
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They are the maximal planar graphs with degeneracy three.
It ranges from 0 for trees to 1 for maximal planar graphs.
They are the chordal maximal planar graphs, the chordal polyhedral graphs, and the planar 3-trees.
Therefore, strangulated graphs include maximal planar graphs.
They are the maximal planar graphs with treewidth three, a class of graphs that can be characterized by their forbidden minors or by their reducability under Y-Δ transforms.
The meshedness coefficient ranges between 0 for trees and 1 for maximal planar graphs.
Apollonian networks are chordal maximal planar graphs, or equivalently planar 3-trees.
However, there are infinitely many 3-connected well-covered maximal planar graphs.
The equivalence of planar 3-trees and chordal maximal planar graphs was stated without proof by Patil 1986.
They characterize these graphs as being the clique-sums of chordal graphs and maximal planar graphs.
The maximal planar graphs without separating triangles that may be formed by repeated splits of this type are sometimes called blocks, although that name has also been used for the biconnected components of a graph that is not itself biconnected.
This follows from the fact that finding Hamiltonian cycles in maximal planar graphs is NP-complete.
However, unlike planar graphs(for which all maximal planar graphs on a given vertex set have the same number of edges as each other), there exist maximal 1-planar graphs(graphs to which no additional edges can be added while preserving 1-planarity) that have significantly fewer than 4n- 8 edges.
This forms an alternative characterization of the Apollonian networks: they are exactly the chordal maximal planar graphs or equivalently the chordal polyhedral graphs. .
Complementing the characterization of well-covered simple polyhedra in three dimensions, researchers have also considered the well-covered simplicial polyhedra, orequivalently the well-covered maximal planar graphs.
There are no well-covered 5-connected maximal planar graphs, and there are only four 4-connected well-covered maximal planar graphs: the graphs of the regular octahedron, the pentagonal dipyramid, the snub disphenoid, and an irregular polyhedron(a nonconvex deltahedron) with 12 vertices, 30 edges, and 20 triangular faces.
The order in which the vertices are added to create the network is therefore a degeneracy ordering, andthe Apollonian networks coincide with the 3-degenerate maximal planar graphs.
Any maximal planar graph may be decomposed into 4-vertex-connected maximal planar subgraphs by splitting it along its separating triangles(triangles that are not faces of the graph): given any non-facial triangle: one can form two smaller maximal planar graphs, one consisting of the part inside the triangle and the other consisting of the part outside the triangle.
Therefore, a normalized meshedness coefficient can be defined as the ratio of these two numbers: α m- n+ 1 2 n- 5.{\displaystyle\alpha={\frac{m-n+1}{2n-5}}.}It varies from 0 for trees to 1 for maximal planar graphs.
Every chordal graph can be decomposed in this way into a clique-sum of complete graphs, and every maximal planar graph can be decomposed into a clique-sum of 4-vertex-connected maximal planar graphs. .
As Seymour& Weaver(1984) show, these are the only possible buildingblocks of strangulated graphs: the strangulated graphs are exactly the graphs that can be formed as clique-sums of complete graphs and maximal planar graphs.
The chordal graphs are exactly the graphs that can be formed by clique-sums of cliques without deleting any edges, andthe strangulated graphs are the graphs that can be formed by clique-sums of cliques and maximal planar graphs without deleting edges.
The graphs in which every induced cycle of length four or greater forms a minimal separator of the graph(its removal partitions the graph into two or more disconnected components, and no subset of the cycle has the same property)are exactly the clique-sums of cliques and maximal planar graphs, again without edge deletions.
Every maximal planar graph, other than K4 W4, contains as a subgraph either W5 or W6.
For instance, a maximal planar graph has such an embedding if and only if it contains a Hamiltonian cycle.
More strongly, by the same argument, if a maximal planar graph has a cycle of length k, it has cycles of all smaller lengths.
Every maximal planar graph with five or more vertices has vertex connectivity 3, 4, or 5.
A maximal planar graph is a planar graph in which all faces, even the outer face, are triangles.
It is named after A. Goldner and Frank Harary,who proved in 1975 that it was the smallest non-Hamiltonian maximal planar graph.
Another more complicated Apollonian network was used by Nishizeki(1980)to provide an example of a 1-tough non-Hamiltonian maximal planar graph.