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Type II Codes over F4

✍ Scribed by Philippe Gaborit; Vera Pless; Patrick Solé; Oliver Atkin

Publisher
Elsevier Science
Year
2002
Tongue
English
Weight
135 KB
Volume
8
Category
Article
ISSN
1071-5797

No coin nor oath required. For personal study only.

✦ Synopsis

The natural analogues of Lee weight and the Gray map over % are introduced. Self-dual codes for the Euclidean scalar product with Lee weights multiple of 4 are called Type II. They produce Type II binary codes by the Gray map. All extended Q-codes of length a multiple of 4 are Type II. This includes quadratic residue codes attached to a prime p,3 (mod 8), certain double circulant codes, and some a$ne invariant codes. A general mass formula is derived, a new upper bound for Euclidean self-dual codes over % is given, and the "rst extremal self-dual [92, 46,16] binary code is built.

2002 Elsevier Science (USA)

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