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A181770 Number of isomorphism classes of racks of order n. 1
1, 1, 2, 6, 19, 74, 353, 2080, 16023 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..8.

Přemysl Jedlička, Agata Pilitowska, Anna Zamojska-Dzienio, Multipermutation set theoretic solutions of the Yang-Baxter equation of level 2, arXiv:1901.01471 [math.QA], 2019.

Sam Nelson, Quandles and Racks

Petr Vojtěchovský, Seung Yeop Yang, Enumeration of racks and quandles up to isomorphism, Mathematics of Computation (2019), American Mathematical Society.

CROSSREFS

Cf. A181769.

Sequence in context: A150118 A150119 A268569 * A138800 A008989 A057240

Adjacent sequences:  A181767 A181768 A181769 * A181771 A181772 A181773

KEYWORD

nonn,hard,more

AUTHOR

James McCarron

STATUS

approved

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Last modified November 13 23:01 EST 2019. Contains 329106 sequences. (Running on oeis4.)