# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a079242 Showing 1-1 of 1 %I A079242 #12 Jan 27 2022 15:42:14 %S A079242 0,0,2,2,8,2,122,2,1682 %N A079242 Number of associative non-commutative non-anti-associative anti-commutative closed binary operations on a set of order n. %H A079242 Index entries for sequences related to semigroups %F A079242 A079230(n) + A079232(n) + A079234(n) + A079236(n) + A079195(n) + A079240(n) + a(n) + A079244(n) + A063524(n) = A002489(n). %F A079242 a(n) = Sum_{k>=1} A079208(n,k)*A079210(n,k). %Y A079242 Cf. A079208, A079243 (isomorphism classes), A079230, A079232, A079234, A079236, A079195, A079240, A079244, A063524. %K A079242 nonn,more %O A079242 0,3 %A A079242 Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003 %E A079242 a(0)=0 prepended and terms a(5)-a(8) added by _Andrew Howroyd_, Jan 27 2022 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE