Korean J. Math. Vol. 25 No. 3 (2017) pp.379-388
DOI: https://doi.org/10.11568/kjm.2017.25.3.379

Self-dual codes over ${\mathbb Z}_{p^2}$ of small lengths

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Whan-hyuk Choi
Young Ho Park


Self-dual codes of lengths less than 5 over ${\mathbb Z}_p$ are completely classified by the second author [The classification of self-dual modular codes, Finite Fields Appl. 17 (2011), 442-460].The number of such self-dual codes are also determined. In this article we will extend the results to classify self-dual codes over ${\mathbb Z}_{p^2}$ of length less than 5 and give the number of codes in each class. Explicit and complete classifications for small $p$'s are also given.

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