A003191 Number of symmetric Latin squares of order 2n with constant diagonal.

1, 1, 6, 5972, 1225533120

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• hard
• nice

References

• N. T. Gridgeman, Latin squares under restriction and a jumboization, J. Rec. Math., 5 (No. 3, 1972), 198-202.
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Index entries for sequences related to Latin squares and rectangles

Extensions

Daniele Degiorgi (degiorgi(AT)inf.ethz.ch) suggests that this is an erroneous version of A000438.