cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A079180 Number of isomorphism classes of anti-associative closed binary operations on a set of order n.

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%I A079180 #21 Sep 22 2024 18:39:13
%S A079180 1,0,2,10,17780
%N A079180 Number of isomorphism classes of anti-associative closed binary operations on a set of order n.
%H A079180 Christian van den Bosch, <a href="https://web.archive.org/web/20071014230143/http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a>
%H A079180 <a href="/index/Se#semigroups">Index entries for sequences related to semigroups</a>
%H A079180 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a>
%F A079180 a(n) = A001329(n) - A079177(n).
%Y A079180 Row sums of A079181.
%Y A079180 Cf. A001329, A079177, A079179 (labeled case).
%K A079180 nonn
%O A079180 0,3
%A A079180 Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003
%E A079180 a(0)=1 prepended and a(1) corrected by _Kamil Zabielski_, Aug 28 2024