A079183 Number of isomorphism classes of non-commutative closed binary operations (groupoids) on a set of order n.

0, 6, 3201, 178937984, 2483527282664925, 14325590003288422852104768, 50976900301814583996024242298024434780, 155682086691137947272042494203068030678979503481450216

Offset: 1

Author

Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003

Keywords

• nonn

Comments

Each a(n) is equal to the sum of the elements in row n of A079184.

Links

• C. van den Bosch, Closed binary operations on small sets
• Index entries for sequences related to groupoids

Crossrefs

Cf. A001329, A001425, A079184.

Formula

a(n) = A001329(n) - A001425(n).

Extensions

Edited and extended by Christian G. Bower, Dec 12 2003