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arXiv · 2003.05556

Quasi-symmetric designs on 56 points

Vedran Krčadinac·Renata Vlahović Kruc
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Abstract

Computational techniques for the construction of quasi-symmetric block designs are explored and applied to the case with $56$ points. One new $(56,16,18)$ and many new $(56,16,6)$ designs are discovered, and non-existence of $(56,12,9)$ and $(56,20,19)$ designs with certain automorphism groups is proved. The number of known symmetric $(78,22,6)$ designs is also significantly increased.

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Vedran Krčadinac, Renata Vlahović Kruc. 2020-03-11. Quasi-symmetric designs on 56 points. https://doi.org/10.3934/amc.2020086

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