A239762 - OEIS

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A239762

Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(f(g(x))) = g(f(x)).

%I #9 Jul 18 2014 12:17:30

%S 1,1,10,159,3568,106545,4062336,192754009

%N Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(f(g(x))) = g(f(x)).

%Y Cf. A181162.

%K nonn,more

%O 0,3

%A _Chad Brewbaker_, Mar 26 2014

%E a(6)-a(7) from _Giovanni Resta_, Mar 28 2014