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Article Contents

# The enumeration of Costas arrays of order 28 and its consequences

• The results of the enumeration of Costas arrays of order 28 are presented: all arrays found are accounted for by the Golomb and Welch construction methods, making 28 the first order (larger than 5) for which no sporadic Costas arrays exist. The enumeration was performed on several computer clusters and required the equivalent of 70 years of single CPU time. Furthermore, a classification of Costas arrays in four classes is proposed, and it is conjectured, based on the results of the enumeration combined with further evidence, that two of them eventually become extinct.
Mathematics Subject Classification: Primary: 05A15, 05B10; Secondary: 05A05, 11B50.

 Citation:

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