%I #12 Dec 25 2023 17:40:02
%S 1,1,8,87,1312,24685,564336,15168811
%N Number of pairs of functions (f,g) on a set of n elements into itself satisfying f(x) = g(f(g(x))).
%F a(n) <= n^2n. - _Charles R Greathouse IV_, Mar 26 2014
%Y Cf. A000248, A000949.
%K nonn,more
%O 0,3
%A _Chad Brewbaker_, Mar 26 2014
%E a(6)-a(7) from _Giovanni Resta_, Mar 28 2014
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