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Number of equivalence classes of unimodular n X n matrices with elements {0, 1}.
2

%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