A079242 Number of associative non-commutative non-anti-associative anti-commutative closed binary operations on a set of order n.

0, 0, 2, 2, 8, 2, 122, 2, 1682

Offset: 0

Author

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

Keywords

• nonn
• more

Links

• Index entries for sequences related to semigroups

Crossrefs

Cf. A079208, A079243 (isomorphism classes), A079230, A079232, A079234, A079236, A079195, A079240, A079244, A063524.

Formula

A079230(n) + A079232(n) + A079234(n) + A079236(n) + A079195(n) + A079240(n) + a(n) + A079244(n) + A063524(n) = A002489(n).

a(n) = Sum_{k>=1} A079208(n,k)*A079210(n,k).

Extensions

a(0)=0 prepended and terms a(5)-a(8) added by Andrew Howroyd, Jan 27 2022