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Number of associative non-commutative non-anti-associative non-anti-commutative closed binary operations on a set of order n.
8

%I #6 Jan 27 2022 15:42:04

%S 0,0,0,48,2344,153000,15875924,7676692856,148188196673360

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

%F A079230(n) + A079232(n) + A079234(n) + A079236(n) + A079195(n) + a(n) + A079242(n) + A079244(n) + A063524(n) = A002489(n).

%F a(n) = Sum_{k>=1} A079207(n,k)*A079210(n,k).

%F a(n) = A023814(n) - A023815(n) - A079242(n). - _Andrew Howroyd_, Jan 27 2022

%Y Cf. A079207, A079241 (isomorphism classes), A079230, A079232, A079234, A079236, A079195, A079242, A079244, A063524.

%K nonn

%O 0,4

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

%E a(0)=0 prepended and a(5)-a(8) added by _Andrew Howroyd_, Jan 27 2022