Abstract
It is well-known that the number of 2-designs with the parameters of a classical point-hyperplane design PG n-1(n, q) grows exponentially. Here we extend this result to the number of 2-designs with the parameters of PG d (n, q), where 2 ≤ d ≤ n − 1. We also establish a characterization of the classical geometric designs in terms of hyperplanes and, in the special case d = 2, also in terms of lines. Finally, we shall discuss some interesting configurations of hyperplanes arising in designs with geometric parameters.
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Communicated by Ron Mullin.
To Spyros Magliveras on the occasion of his 70th birthday.
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Jungnickel, D., Tonchev, V.D. The number of designs with geometric parameters grows exponentially. Des. Codes Cryptogr. 55, 131–140 (2010). https://doi.org/10.1007/s10623-009-9299-6
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DOI: https://doi.org/10.1007/s10623-009-9299-6