A247596 Number of nonisomorphic binary n X n matrices with three 1's per column under row and column permutations.

1, 5, 35, 410, 6178, 122038, 2921607, 81609320, 2588949454, 91699869557, 3582942335285, 153048366545566, 7096576775166579, 355120233277118103, 19084972486216897560, 1096965038775477639368, 67192642484367187943761, 4372413334294007638726854

Offset: 3

Author

Marko Riedel, Sep 21 2014

Keywords

• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 3..40
• StackExchange, How many arrays with crossed cells, order of rows/columns irrelevant, Dec 13 2013

Crossrefs

Column k=3 of A304942.

A diagonal of A305027.

Cf. A247417, A247597, A247598.

Programs

Maple

seq(matrix_marks(n,3), n=3..15); # Using the uploaded program to A247417

PARI

\\ See A304942 for Blocks
a(n) = Blocks(n, n, 3); \\ Andrew Howroyd, May 23 2018

Extensions

Terms a(17) and beyond from Andrew Howroyd, May 23 2018