login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A181592
Number of isomorphism classes of idempotent self-orthogonal Latin squares of order n.
0
1, 0, 0, 1, 2, 0, 8, 8, 283, 243284
OFFSET
1,5
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'.
REFERENCES
G. P. Graham and C. E. Roberts, 2006. Enumeration and isomorphic classification of self-orthogonal Latin squares, Journal of Combinatorial Mathematics and Combinatorial Computing, 59, pp. 101-118.
LINKS
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.
CROSSREFS
Sequence in context: A287855 A287542 A288197 * A332616 A097348 A271034
KEYWORD
nonn
AUTHOR
Martin P Kidd, Nov 01 2010
STATUS
approved