A079179 Number of anti-associative closed binary operations on a set of order n.

1, 0, 2, 52, 421560

Offset

0,3

Links

Table of n, a(n) for n=0..4.

Christian van den Bosch, Closed binary operations on small sets

Index entries for sequences related to groupoids

Formula

a(n) = A002489(n) - A079176(n).

a(n) = Sum_{k>=1} A079181(n,k)*A079210(n,k).

Crossrefs

Cf. A079176, A079180 (isomorphism classes), A079181, A079210.

Sequence in context: A230882 A369089 A216354 * A000654 A061306 A249656

Adjacent sequences: A079176 A079177 A079178 * A079180 A079181 A079182

Keyword

nonn,more

Author

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

Extensions

a(0)=1 prepended and a(1) corrected by Kamil Zabielski, Aug 28 2024

Status

approved