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Symmetric (41,16,6)-designs with a nontrivial automorphism of odd order

✍ Scribed by Edward Spence


Publisher
John Wiley and Sons
Year
1993
Tongue
English
Weight
722 KB
Volume
1
Category
Article
ISSN
1063-8539

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✦ Synopsis


Abstract

If a symmetric (41,16,6)‐design has an automorphism Οƒ of odd prime order q then q = 3 or 5. In the case q = 5 we determine all such designs and find a total of 419 nonisomorphic ones, of which 15 are self‐dual. When q = 3 a combinatorial explosion occurs and the complete classification becomes impracticable. However, we give a characterization in the particular case when Οƒ has order 3 and fixes 11 points, and find that there are 3,076 nonisomorphic designs with this property, all of them being non self‐dual. The other remaining possibility is that Οƒ, of order 3, fixes 5 points. In this case there are 960 orbit matrices (up to isomorphism and duality) and all but one of them yield designs. Here an incomplete investigation shows that in total there are at least 112,000 nonisomorphic designs. Β© 1993 John Wiley & Sons, Inc.


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