Glasnik Matematicki, Vol. 45, No.1 (2010), 1-14.

GRAPHS AND SYMMETRIC DESIGNS CORRESPONDING TO DIFFERENCE SETS IN GROUPS OF ORDER 96

Snježana Braić, Anka Golemac, Joško Mandić and Tanja Vučičić

Abstract.   Using the list of 2607 so far constructed (96,20,4) difference sets as a source, we checked the related symmetric designs upon isomorphism and analyzed their full automorphism groups. New (96,20,4,4) and (96,19,2,4) regular partial difference sets are constructed, together with the corresponding strongly regular graphs.

2000 Mathematics Subject Classification.   05B05, 05B10, 05E30.

Key words and phrases.   Difference set, partial difference set, Cayley graph, symmetric design.

DOI: 10.3336/gm.45.1.01

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