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Choosability
In graph theory, a branch of mathematics, list coloring is a type of graph coloring where each Vertex (graph theory), vertex can be restricted to a list of allowed colors. It was first studied in the 1970s in independent papers by Vadim G. Vizing, Vizing and by Paul Erdős, Erdős, Arthur Rubin, Rubin, and Taylor. Definition Given a graph and given a set of colors for each vertex (called a list), a list coloring is a ''choice function'' that maps every vertex to a color in the list . As with graph coloring, a list coloring is generally assumed to be proper, meaning no two Adjacent vertex, adjacent vertices receive the same color. A graph is -choosable (or -list-colorable) if it has a proper list coloring no matter how one assigns a list of colors to each vertex. The choosability (or list colorability or list chromatic number) of a graph is the least number such that is -choosable. More generally, for a function assigning a positive integer to each vertex , a graph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Rubin
Arthur Leonard Rubin (born 1956) is an American mathematician and aerospace engineer. He was named a Putnam Fellow on four consecutive occasions from 1970 to 1973. Life and career Rubin's mother was Jean E. Rubin, a professor of mathematics at Purdue University Purdue University is a Public university#United States, public Land-grant university, land-grant research university in West Lafayette, Indiana, United States, and the flagship campus of the Purdue University system. The university was founded ..., and his father was Herman Rubin, a professor of statistics at the same university. Arthur co-authored his first paper with his mother in 1969 at the age of 13. He earned his Ph.D. at the California Institute of Technology in 1978, under the direction of Alexander S. Kechris. Rubin unsuccessfully stood as a Libertarian to represent the 55th district in the 1984 California State Assembly elections. Awards and honors As an undergraduate, Rubin was named a Putnam F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
