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A Characterization of Designs Related to an Extremal Doubly-Even Self-Dual Code of Length 48
Masaaki Harada1, Akihiro Munemasa2 and Vladimir D. Tonchev3
1Department of Mathematical Sciences, Yamagata University, Yamagata 990–8560, Japan
2Graduate School of Information Sciences, Tohoku University, Sendai 980–8579, Japan
3Department of Mathematical Sciences, Michigan Technological University, Houghton, MI 49931, USA
Annals of Combinatorics 9 (2) p.89-198 June, 2005
AMS Subject Classification: 05B05, 94B05
The uniqueness of a binary doubly-even self-dual [48, 24, 12] code is used to prove that a self-orthogonal 5-(48, 12, 8) design, as well as some of its derived and residual designs, including a quasi-symmetric 2-(45, 9, 8) design, are all unique up to isomorphism.
Keywords: self-orthogonal design, quasi-symmetric design, self-orthogonal code, extremal selfdual code


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