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A001440 Number of symmetric Costas arrays of order n that are inequivalent under dihedral group. 3
1, 1, 1, 1, 2, 5, 10, 9, 10, 14, 18, 17, 25, 23, 31, 20, 19, 10, 6, 4, 8, 5, 10, 0, 2, 2, 7, 0, 5, 4, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

REFERENCES

CRC Handbook of Combinatorial Designs, C. Colbourn and J. Dinitz, Editors, 1996, IV.7: Costas Arrays by Herbert Taylor (IV.7.6, page 259, Table 2.29).

LINKS

Table of n, a(n) for n=1..32.

CROSSREFS

Cf. A008404, A001441, A001442.

Sequence in context: A126842 A154680 A140469 * A097378 A078310 A138848

Adjacent sequences:  A001437 A001438 A001439 * A001441 A001442 A001443

KEYWORD

nonn,hard,more

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified November 26 18:09 EST 2014. Contains 250083 sequences.