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arXiv · 1509.03731

On the classification of self-dual [20,10,9] codes over GF(7)

Masaaki Harada·Akihiro Munemasa
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Abstract

It is shown that the extended quadratic residue code of length 20 over GF(7) is a unique self-dual [20,10,9] code C such that the lattice obtained from C by Construction A is isomorphic to the 20-dimensional unimodular lattice D_{20}^+, up to equivalence. This is done by converting the classification of such self-dual codes to that of skew-Hadamard matrices of order 20.

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Masaaki Harada, Akihiro Munemasa. 2016-06-06. On the classification of self-dual [20,10,9] codes over GF(7). https://doi.org/10.1016/j.ffa.2016.07.004

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