A178432 Number of isomorphism classes of kei (involutory quandles) of order n.

1, 1, 1, 3, 5, 13, 41, 142, 665, 4288, 36455, 436672, 6926801

Offset: 0

Author

James McCarron, Dec 21 2010

Keywords

• nonn
• hard
• more

Comments

The terms can be calculated by using the Mace4C system which is an isomorph-free model finder. - Choiwah Chow, Oct 30 2023

Links

• P. Jedlicka, A. Pilitowska, D. Stanovsky et al., The structure of medial quandles, arXiv preprint 1409.8396 [math.GR], 2014.
• David Joyce, A classifying invariant of knots, the knot quandle, J. Pure Appl. Algebra 23 (1982) 37-65.
• Sam Nelson, Quandles and Racks
• Mituhisa Takasaki, Abstraction of symmetric transformations (also referenced as Abstractions of symmetric functions), Tohoku Math. J., 49 (1943), 143-207 [in Japanese].

Crossrefs

Cf. A181769, A226173, A242044.

Extensions

a(11)-a(12) from Choiwah Chow, Oct 30 2023