A181593 Number of isomorphism classes of self-orthogonal Latin squares of order n.

1, 0, 0, 6, 22, 0, 3972, 104120, 69112956, 881912947656

Offset

1,4

Comments

A self-orthogonal Latin square (SOLS) is a Latin square orthogonal to its transpose. Two SOLS L and L' are isomorphic if a permutation applied to the rows, columns and symbols of L maps L to L'.

Links

Table of n, a(n) for n=1..10.

A. P. Burger, M. P. Kidd and J. H. van Vuuren, 2010. Enumerasie van self-ortogonale Latynse vierkante van orde 10, LitNet Akademies (Natuurwetenskappe), 7(3), pp. 1-22.

A. P. Burger, M. P. Kidd and J. H. van Vuuren, Enumeration of isomorphism classes of self-orthogonal Latin squares, Ars Combinatoria, 97, pp. 143-152.

Crossrefs

Sequence in context: A261844 A007594 A316775 * A084539 A034124 A055043

Adjacent sequences: A181590 A181591 A181592 * A181594 A181595 A181596

Keyword

hard,more,nonn

Author

Martin P Kidd, Nov 01 2010

Extensions

a(10) from Martin Kidd, Oct 20 2011

Status

approved