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 A255525 #11 Jan 30 2025 13:51:16 %S A255525 1,1,1,1,2,3,4,4,6,9,13,17,27,31,42,57,83,104 %N A255525 1/n! times the number of ordered pairs of permutation functions f,g on n elements where f(g(g(x))) = g(f(f(x))). %C A255525 The fact that A239836(n) is a multiple of n! follows from a general result in group theory due to Solomon. %H A255525 L. Solomon, <a href="http://dx.doi.org/10.1007/BF01899292">The solutions of equations in groups</a>, Arch. Math., V.20. no.3, (1969) 241-247. %F A255525 a(n) = A239836(n)/n!. %Y A255525 Cf. A239836. %K A255525 nonn,more %O A255525 0,5 %A A255525 _Paul Boddington_, Feb 24 2015