A166489 Number of standard SOLSSOMs of order n.

2, 12, 0, 480, 374400, 3528000, 0

Offset

4,1

Comments

A SOLSSOM is a self-orthogonal Latin square with a symmetric orthogonal mate. A SOLSSOM is standard if the self-orthogonal Latin square is idempotent and if the symmetric mate is reduced.

References

A.P. Burger, M.P. Kidd and J.H. van Vuuren, Enumeration of self-orthogonal Latin squares with symmetric orthogonal mates, Submitted to LitNet Akademies (Natuurwetenskappe)

Links

Table of n, a(n) for n=4..10.

Crossrefs

Cf. A166487, A166488, A166490

Sequence in context: A327780 A350258 A364781 * A160367 A016736 A287704

Adjacent sequences: A166486 A166487 A166488 * A166490 A166491 A166492

Keyword

hard,more,nonn

Author

Martin P Kidd, Oct 21 2009

Extensions

Definition and number of order 8 (now includes non-unipotent SOLSSOMs) corrected by Martin P Kidd, Nov 01 2010

Status

approved