1,7

a(n) = 0 whenever n == 2 (mod 3).

a(n) is also the number of unipotent semisymmetric quasigroups of order n+1 and is also the number of semisymmetric loops of order n+1.

Table of n, a(n) for n=1..12.

Brendan D. McKay and Ian M. Wanless, Enumeration of Latin squares with conjugate symmetry, J. Combin. Des. 30 (2022), 105-130.

Cf. A076016-A076020.

Sequence in context: A199933 A078630 A178671 * A179270 A246132 A229827

Adjacent sequences: A076018 A076019 A076020 * A076022 A076023 A076024

nonn,hard,more

Richard C. Schroeppel, Oct 29 2002

a(10)-a(12) from Ian Wanless, Dec 08 2021

approved