In graph theory, Wagner's theorem is a mathematical forbidden graph characterization of planar graphs, named after Klaus Wagner, stating that a finite...
8 KB (939 words) - 09:38, 2 June 2023
the Hohenberg–Mermin–Wagner theorem or Mermin–Wagner theorem (also known as Mermin–Wagner–Berezinskii theorem or Coleman theorem) states that continuous...
30 KB (4,310 words) - 14:08, 6 June 2024
proof, the statement of the theorem was known as Wagner's conjecture after the German mathematician Klaus Wagner, although Wagner said he never conjectured...
19 KB (2,515 words) - 07:16, 15 May 2024
Planar graph (redirect from Wagner theorem)
— • — • ) zero or more times. Instead of considering subdivisions, Wagner's theorem deals with minors: A finite graph is planar if and only if it does...
35 KB (4,471 words) - 04:49, 30 April 2024
this usage has not spread to other places. A closely related result, Wagner's theorem, characterizes the planar graphs by their minors in terms of the same...
9 KB (1,074 words) - 14:25, 7 November 2023
can be formed from a larger graph by contracting and removing edges. Wagner's theorem characterizes the planar graphs as exactly those graphs that do not...
7 KB (554 words) - 20:59, 15 December 2022
bicommutant theorem (functional analysis) Von Neumann's theorem (operator theory) Von Staudt–Clausen theorem (number theory) Wagner's theorem (graph theory)...
72 KB (5,996 words) - 03:48, 5 July 2024
vertices and by contracting edges. The theory of graph minors began with Wagner's theorem that a graph is planar if and only if its minors include neither the...
35 KB (4,046 words) - 19:56, 14 January 2024
the drawing. Outerplanar graphs may be characterized (analogously to Wagner's theorem for planar graphs) by the two forbidden minors K4 and K2,3, or by their...
18 KB (2,034 words) - 23:10, 18 August 2023
contains either K3,3 or the complete graph K5 as a minor; this is Wagner's theorem. Every complete bipartite graph. Kn,n is a Moore graph and a (n,4)-cage...
12 KB (959 words) - 06:10, 4 July 2022