Paul A. Catlin

Paul Allen Catlin ((1948-06-25)June 25, 1948 – (1995-04-20)April 20, 1995) was a mathematician and professor of Mathematics, known for his valuable contributions to graph theory and number theory.

Paul Allen Catlin held a Doctorate in Mathematics degree from Ohio State University, authored over fifty academic papers in number theory and graph theory. Many of his contributions and collaborations have been published in The Fibonacci Quaterly, in The Journal of Number Theory, in the journal of Discrete Mathematics, and many other academic publications. He has co-authored scholarly papers with Arthur M. Hobbs , Béla Bollobás and Paul Erdős , Hong-Jian Lai, Zheng-Yiao Han, and Yehong Shao , among others. He also published papers with G. Neil Robertson, with whom he also completed his dissertation thesis in 1976.

Originally from Bridgeport, Connecticut, Paul A. Catlin majored in Mathematics with a B.A. degree from Carnegie Mellon University in 1970.

From 1972 to 1973, he was a research and teaching assistant at Ohio State University, where he earned the Master of Science degree in Mathematics.

In 1976, he went to work at Wayne State University, where he concentrated the research on chromatic numbers and Brooks' theorem. As a result, Paul A. Catlin published one of the most cited papers in that series: Hajós graph coloring conjecture: variations and counterexamples. , which showed that the conjecture raised by Hugo Hadwiger is further strenghtened not only by $k\leq 4$ but also by $k\geq 7$ , which led to the joint paper written with Paul Erdős and Béla Bollobás entitled Hadwiger's conjecture is true for almost every graph.