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In graph theory, a sum coloring of a graph is a labeling of its vertices by positive integers, with no two adjacent vertices having equal labels, that minimizes the sum of the labels. The minimum sum that can be achieved is called the chromatic sum of the graph. Chromatic sums and sum coloring were introduced by Supowit in 1987 using non-graph-theoretic terminology, and first studied in graph theoretic terms by Ewa Kubicka in her 1989 doctoral thesis.
Maria-Viktoria Hasse was a German mathematician who became the first female professor in the faculty of mathematics and science at TU Dresden. She wrote books on set theory and category theory, and is known as one of the namesakes of the Gallai–Hasse–Roy–Vitaver theorem in graph coloring.
References
- ↑ Prof. Dr. rer. nat. habil. Margit Voigt, University of Applied Sciences Dresden, retrieved 2019-10-01
- ↑ Margit Voigt at the Mathematics Genealogy Project
- 1 2 Aigner, Martin; Ziegler, Günter M. (1999), "Chapter 25: Five-coloring plane graphs", Proofs from The Book, Berlin: Springer-Verlag, pp. 161–164, ISBN 3-540-63698-6, MR 1723092
- ↑ Chartrand, Gary; Lesniak, Linda; Zhang, Ping (2011), Graphs & Digraphs (5th ed.), Boca Raton, FL: CRC Press, p. 378, ISBN 978-1-4398-2627-0, MR 2766107
- ↑ Chen, Louis Hsiao Yun (2001), Challenges for the Twenty-first Century, World Scientific, p. 191, ISBN 9789810246464
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