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%I #12 Oct 27 2019 14:34:05
%S 0,1,1,1,2,5,72,12151,53146457
%N Number of loops of order n, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator).
%F a(n) = (A057771(n)+A057996(n))/2.
%Y For the number of group-like algebraic structures of order n, see:
%Y Semigroups: A027851 or A001423 (commutative: A001426);
%Y Monoids: A058129 or A058133 (commutative: A058131);
%Y Quasigroups: A057991 or A058171 (commutative: A057992);
%Y Loops: A057771 or this sequence (commutative: A089925);
%Y Groups: A000001 (commutative: A000688);
%Y Rings: A027623 or A038036 (commutative: A037289);
%Y Rings with unity: A037291;
%Y Fields: A069513.
%K nonn,hard,more
%O 0,5
%A _Jianing Song_, Oct 26 2019