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A309089
a(n) is the number of absolute values of determinants that come from a unique isotopy class of order n Latin squares.
1
1, 1, 1, 2, 5, 85, 124
OFFSET
1,4
COMMENTS
We apply every symbol permutation on the representatives of isotopic classes to generate Latin square of order n and calculate the determinants.
These results are based upon work supported by the National Science Foundation under the grants numbered DMS-1852378 and DMS-1560019.
EXAMPLE
For n=4, the determinants 80 and 160 are produced by a unique isotopic class which has [[1, 2, 3, 4], [2, 4, 1, 3], [3, 1, 4, 2], [4, 3, 2, 1]] as a representative. All other determinants are produced by multiple isotopic classes. Therefore a(4)=2.
PROG
(Sage) # See Maldonado link
CROSSREFS
KEYWORD
nonn,hard,more
STATUS
approved