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Rudolf Halin
Rudolf Halin (February 3, 1934 – November 14, 2014) was a German graph theory, graph theorist, known for defining the End (graph theory), ends of infinite graphs, for Halin's grid theorem, for extending Menger's theorem to infinite graphs, and for his early research on treewidth and tree decomposition. He is also the namesake of Halin graphs, a class of planar graphs constructed from tree (graph theory), trees by adding a cycle through the leaves of the given tree; earlier researchers had studied the subclass of cubic graph, cubic Halin graphs but Halin was the first to study this class of graphs in full generality. Life Halin was born on February 3, 1934 in Uerdingen.. Date corrected in a follow-up email from Diestel. Birthplace from his books ''Graphentheorie I, II''. He earned his doctorate from the University of Cologne in 1962, under the supervision of Klaus Wagner and Karl Dörge, after which he joined the faculty of the University of Hamburg. He died on November 14, 2014, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graph Theory
In mathematics, graph theory is the study of ''graphs'', which are mathematical structures used to model pairwise relations between objects. A graph in this context is made up of '' vertices'' (also called ''nodes'' or ''points'') which are connected by '' edges'' (also called ''links'' or ''lines''). A distinction is made between undirected graphs, where edges link two vertices symmetrically, and directed graphs, where edges link two vertices asymmetrically. Graphs are one of the principal objects of study in discrete mathematics. Definitions Definitions in graph theory vary. The following are some of the more basic ways of defining graphs and related mathematical structures. Graph In one restricted but very common sense of the term, a graph is an ordered pair G=(V,E) comprising: * V, a set of vertices (also called nodes or points); * E \subseteq \, a set of edges (also called links or lines), which are unordered pairs of vertices (that is, an edge is associated with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
