Non Existence of Triangle Free Quasi-symmetric Designs
The following two results are proved. Let D be a triangle free quasi-symmetric design with k=2y−x and x≥ 1 then D is a trivial design with v=5 and k=3. There do no exist triangle free quasi-symmetric designs with x≥ 1 and λ=y or λ=y−1.
KeywordsQuasi-symmetric designs strongly regular graphs
AMS Classification:Primary 05 B05 Secondary 05 B30 05 B25
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