A363862 - OEIS

A363862

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

1, 2, 7, 49, 831, 39637, 5593528, 2363927011

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OFFSET

1,2

COMMENTS

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.

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

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]].

CROSSREFS

A306837 gives the total counts rather than equivalence classes.

Sequence in context: A186860 A139008 A058721 * A340027 A362340 A324513

Adjacent sequences: A363859 A363860 A363861 * A363863 A363864 A363865

KEYWORD

nonn,hard,more

AUTHOR

Brendan McKay, Jun 25 2023

STATUS

approved