English

Pappus-Desargues digraph confrontation

Combinatorics 2012-06-15 v9

Abstract

Like the Coxeter graph became reattached into the Klein graph in [2], the Levi graphs of the 939_3 and 10310_3 self-dual configurations, known as the Pappus and Desargues (kk-transitive) graphs P\mathcal P and D\mathcal D (where k=3k=3), also admit reattachments of the distance-(k1)(k-1) graphs of half of their oriented shortest cycles via orientation assignments on their common (k1)(k-1)-arcs, concurrent for P{\mathcal P} and opposite for D\mathcal D, now into 2 disjoint copies of their corresponding Menger graphs. Here, P\mathcal P is the unique cubic distance-transitive (or CDT) graph with the concurrent-reattachment behavior while D\mathcal D is one of 7 CDT graphs with the opposite-reattachment behavior, that include the Coxeter graph. Thus, P\mathcal P and D\mathcal D confront each other in these respects, obtained via C\mathcal C-ultrahomogeneous graph techniques [3,4] that allow to characterize the obtained reattachment Menger graphs in the same terms.

Cite

@article{arxiv.0904.1096,
  title  = {Pappus-Desargues digraph confrontation},
  author = {Italo J. Dejter},
  journal= {arXiv preprint arXiv:0904.1096},
  year   = {2012}
}

Comments

11 pages, 3 figures, 4 tables

R2 v1 2026-06-21T12:48:58.530Z