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A226173
The number of connected keis (involutory quandles) of order n.
1
1, 0, 1, 0, 1, 1, 1, 0, 2, 1, 1, 3, 1, 0, 4, 0, 1, 3, 1, 3, 4, 0, 1, 10, 2, 0, 8, 2, 1, 10, 1, 0, 2, 0, 1, 16, 1, 0, 2, 8, 1, 8, 1, 0, 13, 0, 1
OFFSET
1,9
COMMENTS
A quandle (Q,*) is a kei (also called involutory quandle) if for all x,y in Q we have (x*y)*y = x, that is, all right translations R_a: x-> x*a, are involutions.
REFERENCES
J. S. Carter, A survey of quandle ideas. in: Kauffman, Louis H. (ed.) et al., Introductory lectures on knot theory, Series on Knots and Everything 46, World Scientific (2012), 22--53.
W. E. Clark, M. Elhamdadi, M. Saito and T. Yeatman, Quandle colorings of knots and applications. J. Knot Theory Ramifications 23/6 (2014), 1450035.
LINKS
N. Andruskiewitsch, M. Graňa, From racks to pointed Hopf algebras, Adv. Math. 178/2 (2003), 177-243.
J. Scott Carter, A Survey of Quandle Ideas, arXiv:1002.4429 [math.GT], Feb 2010
W. E. Clark, M. Elhamdadi, M. Saito, T. Yeatman, Quandle Colorings of Knots and Applications, arXiv preprint arXiv:1312.3307, 2013
A. Hulpke, D. Stanovský, P. Vojtěchovský, Connected quandles and transitive groups, arXiv:1409.2249 [math.GR], Sep 2014, to appear in J. Pure Appl. Algebra.
CROSSREFS
Cf. A181771 (number of connected quandles of order n).
See also Index to OEIS under quandles.
Sequence in context: A114118 A146014 A344824 * A212633 A202241 A248156
KEYWORD
nonn,more,hard
AUTHOR
W. Edwin Clark, May 29 2013
EXTENSIONS
a(36)-a(47) (calculated by methods described in Hulpke, Stanovský, Vojtěchovský link) from David Stanovsky, Jun 02 2015
STATUS
approved