A086829 Number of n X n matrices on n^2 distinct symbols modulo rotations and reflections.

1, 3, 45360, 2615348736000, 1938901255416373248000000, 46499165848737652183499931018854400000000, 76035233004283445109031520415161922110944103922401280000000000

Offset

1,2

Comments

Also the number of distinct adjacency matrices on the n X n grid graph P_n x P_n. - Eric W. Weisstein, May 01 2017

Links

Table of n, a(n) for n=1..7.

Eric Weisstein's World of Mathematics, Adjacency Matrix

Eric Weisstein's World of Mathematics, Grid Graph

Eric Weisstein's World of Mathematics, Square Matrix

Formula

a(n) = (n^2)!/8, n>1. - Vladeta Jovovic, Aug 10 2003

Mathematica

Table[Piecewise[{{1, n == 1}}, (n^2)!/8], {n, 7}]

Crossrefs

Cf. A087074.

Sequence in context: A140656 A135760 A003541 * A190722 A171365 A115976

Adjacent sequences: A086826 A086827 A086828 * A086830 A086831 A086832

Keyword

nonn,easy

Author

Eric W. Weisstein, Aug 08 2003

Extensions

More terms from Sam Alexander, Feb 27 2004

Status

approved