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A309257
a(n) is the minimum positive value of the determinants of circulant order n Latin squares.
2
1, 3, 18, 80, 75, 3087, 196, 1440, 405, 6325, 726, 7488, 1183, 11025, 1800
OFFSET
1,2
COMMENTS
These results are based upon work supported by the National Science Foundation under the grants numbered DMS-1852378 and DMS-1560019.
EXAMPLE
For n=2, a(2)=3 is the minimum absolute value determinant of a back circulant Latin square of order 2. An example of one such matrix is [[2 1], [1 2]].
For n=5, a(5)= 75 is the minimum absolute value determinant of a back circulant Latin square of order 5. An example of one such matrix is [[1, 2, 4, 5, 3], [3, 1, 2, 4, 5], [5, 3, 1, 2, 4], [4, 5, 3, 1, 2], [2, 4, 5, 3, 1]] has determinant 75.
PROG
(Sage) See Maldonado link.
CROSSREFS
KEYWORD
nonn,more,hard
EXTENSIONS
Modified title and a(8)-a(13) from Hugo Pfoertner, Oct 01 2019
a(14) from Hugo Pfoertner, Oct 07 2019
a(15) from Hugo Pfoertner, Oct 13 2019
STATUS
approved