When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Lattice graph - Wikipedia

    en.wikipedia.org/wiki/Lattice_graph

    Square grid graph Triangular grid graph. In graph theory, a lattice graph, mesh graph, or grid graph is a graph whose drawing, embedded in some Euclidean space ⁠ ⁠, forms a regular tiling. This implies that the group of bijective transformations that send the graph to itself is a lattice in the group-theoretical sense.

  3. Bramble (graph theory) - Wikipedia

    en.wikipedia.org/wiki/Bramble_(graph_theory)

    A bramble of order four in a 3×3 grid graph, consisting of six mutually touching connected subgraphs. In graph theory, a bramble for an undirected graph G is a family of connected subgraphs of G that all touch each other: for every pair of disjoint subgraphs, there must exist an edge in G that has one endpoint in each subgraph.

  4. Halin's grid theorem - Wikipedia

    en.wikipedia.org/wiki/Halin's_grid_theorem

    In graph theory, a branch of mathematics, Halin's grid theorem states that the infinite graphs with thick ends are exactly the graphs containing subdivisions of the hexagonal tiling of the plane. [1] It was published by Rudolf Halin ( 1965 ), and is a precursor to the work of Robertson and Seymour linking treewidth to large grid minors , which ...

  5. Treewidth - Wikipedia

    en.wikipedia.org/wiki/Treewidth

    The planar graphs do not have bounded treewidth, because the n × n grid graph is a planar graph with treewidth exactly n. Therefore, if F is a minor-closed graph family with bounded treewidth, it cannot include all planar graphs.

  6. Girth (graph theory) - Wikipedia

    en.wikipedia.org/wiki/Girth_(graph_theory)

    In graph theory, the girth of an undirected graph is the length of a shortest cycle contained in the graph. [1] If the graph does not contain any cycles (that is, it is a forest), its girth is defined to be infinity. [2] For example, a 4-cycle (square) has girth 4. A grid has girth 4 as well, and a triangular mesh has girth 3.

  7. Planar separator theorem - Wikipedia

    en.wikipedia.org/wiki/Planar_separator_theorem

    A planar separator for a grid graph. Consider a grid graph with rows and columns; the number of vertices equals .For instance, in the illustration, =, =, and = =.If is odd, there is a single central row, and otherwise there are two rows equally close to the center; similarly, if is odd, there is a single central column, and otherwise there are two columns equally close to the center.

  8. Graph theory - Wikipedia

    en.wikipedia.org/wiki/Graph_theory

    A graph with 6 vertices and 7 edges. In mathematics and computer science, graph theory is the study of graphs, which are mathematical structures used to model pairwise relations between objects.

  9. Glossary of graph theory - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_graph_theory

    3. A square grid graph is a lattice graph defined from points in the plane with integer coordinates connected by unit-length edges. stable A stable set is a synonym for an independent set. star A star is a tree with one internal vertex; equivalently, it is a complete bipartite graph K 1,n for some n ≥ 2. The special case of a star with three ...