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

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

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.


self-dual codes, modular codes

Subject classification

11T71, 94B60.


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