Ads
related to: extremal graphs for intersecting triangles worksheet solutions free
Search results
Results from the WOW.Com Content Network
The Turán graph T(n,r) is an example of an extremal graph. It has the maximum possible number of edges for a graph on n vertices without (r + 1)-cliques. This is T(13,4). Extremal graph theory is a branch of combinatorics, itself an area of mathematics, that lies at the intersection of extremal combinatorics and graph theory. In essence ...
The Grötzsch graph is a triangle-free graph that cannot be colored with fewer than four colors. Much research about triangle-free graphs has focused on graph coloring. Every bipartite graph (that is, every 2-colorable graph) is triangle-free, and Grötzsch's theorem states that every triangle-free planar graph may be 3-colored. [8]
The extremal number (,) is the maximum number of edges in an -vertex graph containing no subgraph isomorphic to . is the complete graph on vertices. (,) is the Turán graph: a complete -partite graph on vertices, with vertices distributed between parts as equally as possible.
In graph theory, Turán's theorem bounds the number of edges that can be included in an undirected graph that does not have a complete subgraph of a given size. It is one of the central results of extremal graph theory, an area studying the largest or smallest graphs with given properties, and is a special case of the forbidden subgraph problem on the maximum number of edges in a graph that ...
A balanced tripartite graph with the unique triangle property can be made into a partitioned bipartite graph by removing one of its three subsets of vertices, and making an induced matching on the neighbors of each removed vertex. To convert a graph with a unique triangle per edge into a triple system, let the triples be the triangles of the graph.
In extremal graph theory, the Erdős–Stone theorem is an asymptotic result generalising Turán's theorem to bound the number of edges in an H-free graph for a non-complete graph H. It is named after Paul Erdős and Arthur Stone, who proved it in 1946, [1] and it has been described as the “fundamental theorem of extremal graph theory”. [2]
Ramsey-Turán theory is a subfield of extremal graph theory. It studies common generalizations of Ramsey's theorem and Turán's theorem. In brief, Ramsey-Turán theory asks for the maximum number of edges a graph which satisfies constraints on its subgraphs and structure can have. The theory organizes many natural questions which arise in ...
Packing and covering triangles in the complete graph. The maximum number of edge-disjoint triangles in this graph is two (left). If four edges are removed from the graph (red edges, right), the remaining subgraph becomes triangle-free, and more strongly bipartite (as shown by the blue and yellow vertex coloring). According to Tuza's conjecture ...
Ads
related to: extremal graphs for intersecting triangles worksheet solutions free