Abstract
We study combinatorial configurations with the associated point and line graphs being strongly regular. Examples not belonging to known classes such as partial geometries and their generalizations or elliptic semiplanes are constructed. Necessary existence conditions are proved and a table of feasible parameters of such configurations with at most 200 points is presented. Non-existence of some configurations with feasible parameters is proved.
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Notes
We will always use the term line graph in this sense, and not in the sense of graph theory (the line graph L(G) of a graph G).
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Vedran Krčadinac was supported by the Croatian Science Foundation under the Projects 6732 and 9752.
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Abreu, M., Funk, M., Krčadinac, V. et al. Strongly regular configurations. Des. Codes Cryptogr. 90, 1881–1897 (2022). https://doi.org/10.1007/s10623-022-01080-w
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DOI: https://doi.org/10.1007/s10623-022-01080-w