Pseudocyclic association schemes arising from the actions of PGL ( 2 , 2 m ) and P L ( 2 , 2 m )
نویسندگان
چکیده
The action of PGL(2,2m) on the set of exterior lines to a nonsingular conic in PG(2,2m) affords an association scheme, which was shown to be pseudocyclic in [H.D.L. Hollmann, Association schemes, Master thesis, Eindhoven University of Technology, 1982]. It was further conjectured in [H.D.L. Hollmann, Association schemes, Master thesis, Eindhoven University of Technology, 1982] that the orbital scheme of P L(2,2m) on the set of exterior lines to a nonsingular conic in PG(2,2m) is also pseudocyclic if m is an odd prime. We confirm this conjecture in this paper. As a by-product, we obtain a class of Latin square type strongly regular graphs on nonprime-power number of points. © 2005 Elsevier Inc. All rights reserved.
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