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%I #7 Jun 25 2023 05:58:59
%S 1,2,7,49,831,39637,5593528,2363927011
%N Number of equivalence classes of unimodular n X n matrices with elements {0, 1}.
%C An integer matrix is unimodular if its determinant is -1 or +1. Two matrices are equivalent if one can be obtained from the other by permuting rows and columns.
%e For n=1, the only example is [1]. For n=2, representatives of the equivalence classes are [[1,0],[0,1]] and [[1,1],[0,1]].
%Y A306837 gives the total counts rather than equivalence classes.
%K nonn,hard,more
%O 1,2
%A _Brendan McKay_, Jun 25 2023