Covers of graphs and EGQs. (English) Zbl 0763.05077
Summary: The purposes of this paper is the construction of some new extended generalized quadrangles, as covers of known examples. The construction requires the vanishing of cohomology of certain simplicial complexes. One of the constructions generalizes to give some distance-regular antipodal covers of complete graphs, some of which also appear to be new.
MSC:
| 05C70 | Edge subsets with special properties (factorization, matching, partitioning, covering and packing, etc.) |
| 51E12 | Generalized quadrangles and generalized polygons in finite geometry |
Keywords:
extended generalized quadrangles; covers; distance-regular antipodal covers; complete graphsReferences:
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