Annals of Combinatorics

, 15:267 | Cite as

Cores of Geometric Graphs

  • Chris GodsilEmail author
  • Gordon F. Royle


Cameron and Kazanidis have recently shown that rank-three graphs are either cores or have complete cores, and they asked whether this holds for all strongly regular graphs. We prove that this is true for the point graphs and line graphs of generalized quadrangles and that when the number of points is sufficiently large, it is also true for the block graphs of Steiner systems and orthogonal arrays.

Mathematics Subject Classification

05C15 51E14 


graph homomorphism core strongly regular graph partial geometry 


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Copyright information

© Springer Basel AG 2011

Authors and Affiliations

  1. 1.Department of Combinatorics and OptimizationUniversity of WaterlooWaterlooCanada
  2. 2.School of Mathematics and StatisticsUniversity of Western AustraliaPerthAustralia

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