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A quasi-symmetric 2-(49,9,6) design

✍ Scribed by Masaaki Harada; Akihiro Munemasa

Publisher: John Wiley and Sons
Year: 2002
Tongue: English
Weight: 79 KB
Volume: 10
Category: Article
ISSN: 1063-8539
DOI: 10.1002/jcd.10007

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✦ Synopsis

Abstract

Huffman and Tonchev discovered four non‐isomorphic quasi‐symmetric 2‐(49,9,6) designs. They arise from extremal self‐dual [50,25,10] codes with a certain weight enumerator. In this note, a new quasi‐symmetric 2‐(49,9,6) design is constructed. This is established by finding a new extremal self‐dual [50,25,10] code as a neighbor of one of the four extremal codes discovered by Huffman and Tonchev. A number of new extremal self‐dual [50,25,10] codes with other weight enumerators are also found. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 173–179, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10007

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