The flag-transitive symmetric designs with 45 points, blocks of size 12, and 3 blocks on every point pair
نویسنده
چکیده
We construct two flag-transitive designs with the parameters of the title, and prove that these are the only two examples. One is pointprimitive and related to unitary geometry, while the other is pointimprimitive and constructed from a one-dimensional affine space. This classification may be contrasted with a construction by Mathon and Spence in 1996 of more than 3700 designs with these parameters, almost a third of which had a trivial automorphism group.
منابع مشابه
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ورودعنوان ژورنال:
- Des. Codes Cryptography
دوره 44 شماره
صفحات -
تاریخ انتشار 2007