Abstract
The designPG 2 (4,q) of the points and planes ofPG (4,q) forms a quasi-symmetric 2-design with block intersection numbersx=1 andy=q+1. We give some characterizations of quasi-symmetric designs withx=1 which have a spread through a fixed point. For instance, it is proved that if such a designD is also smooth, thenD≅PG 2 (4,q).
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Communicated by R. Mullin
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Sane, S.S., Shrikhande, M.S. Some characterizations of quasi-symmetric designs with a spread. Des Codes Crypt 3, 155–166 (1993). https://doi.org/10.1007/BF01388414
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DOI: https://doi.org/10.1007/BF01388414