## Abstract In this article, we introduce a new orderly backtrack algorithm with efficient isomorph rejection for classification of __t__‐designs. As an application, we classify all simple 2‐(13,3,2) designs with nontrivial automorphism groups. The total number of such designs amounts to 1,897,386.
A Series of Hadamard Designs with Large Automorphism Groups
✍ Scribed by Dieter Held; Mario-Osvin Pavčević
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 78 KB
- Volume
- 234
- Category
- Article
- ISSN
- 0021-8693
No coin nor oath required. For personal study only.
✦ Synopsis
for helmut wielandt on his 90th birthday Whilst studying a certain symmetric 99 49 24 -design acted upon by a Frobenius group of order 21, it became clear that the design would be a member of an infinite series of symmetric 2q 2 + 1 q 2 q 2 -1 /2 -designs for odd prime powers q. In this note, we present the definition of the series and give some information about the automorphism groups of its members.
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