A242275 Number of isomorphism classes of 2-reductive abelian/medial quandles.

1, 1, 2, 5, 15, 55, 246, 1398, 10301, 98532, 1246479, 20837171, 466087624, 13943041873, 563753074915, 30784745506212

Offset

1,3

Comments

Both names "abelian" and "medial" refer to the identity (xy)(uv)=(xu)(yv). A quandle is called 2-reductive if all orbits are projection quandles.

Links

Table of n, a(n) for n=1..16.

P. Jedlička, A. Pilitowska, D. Stanovský, A. Zamojska-Dzienio, The structure of medial quandles, arXiv:1409.8396 [math.GR], 2014.

David Stanovský, Calculating with quandles GAP code to calculate the numbers.

Crossrefs

Cf. A165200.

Sequence in context: A104429 A109319 A059219 * A363200 A137533 A121392

Adjacent sequences: A242272 A242273 A242274 * A242276 A242277 A242278

Keyword

nonn,hard

Author

David Stanovsky, Oct 01 2014

Status

approved