cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A306837 Number of unimodular n X n matrices with elements {0, 1}.

Original entry on oeis.org

1, 6, 168, 20040, 9702720, 18480102480, 135491563468800, 3766962568171582080
Offset: 1

Views

Author

Steven E. Thornton, Mar 12 2019

Keywords

Comments

An integer matrix is unimodular if its determinant is -1 or +1.

Links

Crossrefs

Number of different values taken by the determinant is in A089472.
Maximum determinant is in A003432.
A363862 gives equivalence classes up to row and column permutation.

Extensions

a(7) and a(8) from Brendan McKay, Jun 25 2023

A363884 Number of connected bipartite graphs on 2n nodes with a distinguished partite set of size n and with a unimodular reduced adjacency matrix.

Original entry on oeis.org

1, 1, 5, 41, 777, 38749, 5552904, 2358289931
Offset: 1

Views

Author

Max Alekseyev, Jun 25 2023

Keywords

Crossrefs

Inverse Euler transform of A363862.
Cf. A306837, A363846.
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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