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%I #12 May 20 2022 13:00:47
%S 0,0,2,2,0,8,66,3115,0,1,14,18,270,467,48260,178888824
%N Number of isomorphism classes of non-associative non-commutative closed binary operations on a set of order n, listed by class size.
%C Elements per row: 1,1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!)
%H C. van den Bosch, <a href="http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a>
%H <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a>
%F T(n,k) + A079197(n,k) + A079200(n,k) + A079201(n,k) = A079171(n,k).
%F A079192(n,k) = Sum_{k>=1} T(n,k)*A079210(n,k).
%e Triangle T(n,k) begins:
%e 0;
%e 0;
%e 2, 2;
%e 0, 8, 66, 3115;
%e 0, 1, 14, 18, 270, 467, 48260, 178888824;
%e ...
%Y Row sums give A079193.
%Y Cf. A027423 (row lengths), A079171, A079192, A079197, A079200, A079201, A079210.
%K nonn,tabf,hard,more
%O 0,3
%A Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003
%E a(0)=0 prepended by _Andrew Howroyd_, Jan 26 2022
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