Gerhard Ringel (October 28, 1919 in Kollnbrunn, Austria – June 24, 2008 in Santa Cruz, California) was a German mathematician. He was one of the pioneers...
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prevention Faye Ringel, former American professor of humanities at the United States Coast Guard Academy and an author Gerhard Ringel (1919–2008), German...
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Heawood conjecture (redirect from Ringel–Youngs theorem)
conjecture was formulated in 1890 by P.J. Heawood and proven in 1968 by Gerhard Ringel and J.W.T. Youngs. One case, the non-orientable Klein bottle, proved...
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coloring problem (solved by the four color theorem), and was posed by Gerhard Ringel in 1959. An intuitive form of the problem asks how many colors are needed...
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Graceful labeling (redirect from Ringel-Kotzig conjecture)
graph theory is the graceful tree conjecture or Ringel–Kotzig conjecture, named after Gerhard Ringel and Anton Kotzig, and sometimes abbreviated GTC (not...
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explicit use of homology. Sperner's students included Kurt Leichtweiss and Gerhard Ringel. Ein Satz über Untermengen einer endlichen Menge. Math. Z. 27 (1928)...
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conjectures (now theorems). Bernhard Riemann 24900 Ringel–Kotzig conjecture graph theory Gerhard Ringel and Anton Kotzig 187 Rudin's conjecture additive...
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undergraduate-level textbook on graph theory by Nora Hartsfield and Gerhard Ringel. It was published in 1990 by Academic Press with a revised edition in...
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Heawood in 1890 and, after contributions by several people, proved by Gerhard Ringel and J. W. T. Youngs in 1968. The only exception to the formula is the...
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problem on the chromatic number of biplanar graphs, posed in 1959 by Gerhard Ringel, and on a related 1962 conjecture of Frank Harary: Every graph on nine...
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Reingold Jennifer Rexford Dana S. Richards Frigyes Riesz John Rigby Gerhard Ringel Alexander Rinnooy Kan John Riordan Jorma Rissanen Ivan Rival Ron Rivest...
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never exceeds 6 {\displaystyle 6} . Later it was proved in the works of Gerhard Ringel, J. W. T. Youngs, and other contributors that the complete graph with...
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the concept was already extensively used under the name "rotation" by Gerhard Ringel and J.W.T. Youngs in their famous solution of the Heawood map-coloring...
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Research Institute for Mathematics, where the problem was posed in 1967 by Gerhard Ringel. It is known to be true for all sufficiently-large complete graphs....
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Berlekamp, John L. Selfridge, Kenneth Falconer, Frank Harary, Lee Sallows, Gerhard Ringel, Béla Bollobás, C. B. Lacampagne, Bruce Sagan, and Neil Sloane. Over...
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17 percent of the municipality is forested. Bad Pirawarth Kollnbrunn Gerhard Ringel, born at Kollnbrunn "Dauersiedlungsraum der Gemeinden Politischen Bezirke...
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discovered until eleven years after publication, nearly simultaneously by Gerhard Ringel and Paul Kainen. Nevertheless, it is conjectured that Zarankiewicz's...
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Derek Dougan, Northern Irish footballer and manager (b. 1938) 2008 – Gerhard Ringel, Austrian mathematician and academic (b. 1919) 2009 – Roméo LeBlanc...
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are named after him. These include the Ringel–Kotzig conjecture on graceful labeling of trees (with Gerhard Ringel); Kotzig's conjecture on regularly path...
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molecule with a grant from the National Institutes of Health. For Dr. Gerhard Ringel, head of the Math department at UCSC, Risan worked on embeddings on...
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problem for Frechét Surfaces, Memoirs American Mathematical Society 1951 Ringel, Gerhard; Youngs, J.W.T. (1968). "Solution of the Heawood map-coloring problem"...
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Richarz Eugen Richter Hans Riegel Charles Pierre Henri Rieu Matthias Ring Gerhard Ringel Albrecht Ritschl Otto Ritschl Franz Ritter Emil Ritterling Robert Kurt...
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with Robert Adams), Galerie Thomas Zander, Köln; Lagune, Galerie Felix Ringel, Düsseldorf; Journal Entries, Heni Publishing, London 2019: deeply unaware...
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magic square is semimagic, but not vice versa. Nora Hartsfield and Gerhard Ringel (1994, 2003), Pearls in Graph Theory, revised edition. Dover Publications...
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the proof of the Heawood conjecture on coloring graphs on surfaces by Gerhard Ringel and Ted Youngs. And Günter M. Ziegler complains that many claims are...
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39 (1): 3–6, hdl:10338.dmlcz/136481, MR 1016323 Hartsfeld, Nora; Ringel, Gerhard (1991), "Clean triangulations", Combinatorica, 11 (2): 145–155, doi:10...
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FORVM (section Gerhard Oberschlick era (1986–1995))
1954 to 1965. In 1965 Günther Nenning took over as editor and in 1986 Gerhard Oberschlick. The magazine was distributed internationally and instigated...
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the town of Santhià, on the way to Milan, resulting in 48 deaths. Julius Ringel (1 November 1940 – 10 February 1944) Max-Günther Schrank (10 February 1944...
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"Regular toroids" (PDF), Structural Topology, 13: 69–80 Jungerman, M.; Ringel, Gerhard (1980), "Minimal triangulations on orientable surfaces", Acta Mathematica...
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Retrieved 2023-06-09. Park, Joon Sung; O'Brien, Joseph C.; Cai, Carrie J.; Ringel Morris, Meredith; Liang, Percy; Bernstein, Michael S. (2023-04-01). "Generative...
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