TOPICS
Search

Berman-Gévay-Pisanski Configuration


BermanGevayPisanskiConfiguration

The Berman-Gévay-Pisanski configuration is the term used in this work for the geometric, self-dual 21_4 polycyclic configuration denoted B(21_4) by Berman et al. (2024) and having threefold rotational symmetry. The Grünbaum-Rigby configuration is also a geometric 21_4 polycyclic configuration, but the two are not combinatorially isomorphic.

The Berman-Gévay-Pisanski and Grünbaum-Rigby configurations are exactly the two geometric 21_4 polycyclic configurations, while there are 17 combinatorial polycyclic configurations of order 21_4 (Berman et al. 2024). The construction of B(21_4) disproved the conjecture of Grünbaum and Rigby (1990) that no other 21_4 configuration exists.

The Levi graph of the configuration, known in this work as the Berman-Gévay-Pisanski graph, is a connected quartic graph and bipartite graph with 42 vertices and 84 edges. Its automorphism group has order 12, compared with 672 for the Grünbaum-Rigby graph. Thus, just as the Berman-Gévay-Pisanski and Grünbaum-Rigby configurations are distinct, their Levi graphs are nonisomorphic (Berman et al. 2024).


See also

Berman Configurations, Berman-Gévay-Pisanski Graph, Bokowski-Pilaud Configuration, Bokowski-Schewe Configuration, Configuration, Grünbaum 204 Configuration, Grünbaum-Rigby Configuration, Grünbaum-Rigby Graph, Levi Graph, Polycyclic Configuration

Explore with Wolfram|Alpha

References

Berman, L. W.; Gévay, G.; and Pisanski, T. "On a New (21_4) Polycyclic Configuration." Electron. J. Combin. 31, #P4.54, 2024. https://doi.org/10.37236/12405.Grünbaum, B. and Rigby, J. F. "The Real Configuration (21_4)." J. London Math. Soc. 41, 336-346, 1990. https://doi.org/10.1112/jlms/s2-41.2.336.

Cite this as:

Weisstein, Eric W. "Berman-Gévay-Pisanski Configuration." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Berman-Gevay-PisanskiConfiguration.html

Subject classifications