A266168 Number of isotopism classes of ordered pairs of orthogonal Latin squares.

1, 0, 1, 1, 3, 0, 34, 45927, 2203310919

Offset

1,5

Comments

The following operations produce things that are counted as equivalent: simultaneous permutation of the rows or columns of both squares; permutation of the symbols within either square.

Links

Table of n, a(n) for n=1..9.

J. Egan and I. M. Wanless, Enumeration of MOLS of small order, Mathematics of Computation 85, 2016, 799-824.

Ian Wanless, Data on MOLS

Crossrefs

Cf. A129732, A266166, A266167.

Sequence in context: A145222 A058833 A368284 * A276913 A012775 A157308

Adjacent sequences: A266165 A266166 A266167 * A266169 A266170 A266171

Keyword

nonn,more

Author

Ian Wanless, Dec 22 2015

Status

approved