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.
%I A079187 #10 Aug 03 2025 23:40:47 %S A079187 1,4,2334,147124304,2216860823492185,13395780829563177947362200, %T A079187 48974776899548402559651008669035131863, %U A079187 151979850442580207421627199010701131897617064179661376,534046142973031436667769900555231150876473571233474760878454735694121879 %N A079187 Number of isomorphism classes of non-anti-commutative closed binary operations (groupoids) on a set of order n. %C A079187 Each a(n) is equal to the sum of the elements in row n of A079188. %H A079187 C. van den Bosch, <a href="http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a> %H A079187 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a> %F A079187 a(n) = A001329(n) - A079190(n), n > 1. %Y A079187 Cf. A079186, A079188, A079190. %K A079187 nonn %O A079187 1,2 %A A079187 Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003 %E A079187 Edited, corrected and extended by _Christian G. Bower_, Dec 12 2003 %E A079187 a(9) from _Sean A. Irvine_, Aug 03 2025