Number of ordered pairs of permutation functions (f,g) on n elements satisfying f(x) = f(g(g(x))).
A239840
Number of ordered pairs of permutation functions (f,g) on n elements satisfying f(x) = f(g(g(x))).
Terms
- a(0) =1a(1) =1a(2) =4a(3) =24a(4) =240a(5) =3120a(6) =54720a(7) =1169280a(8) =30804480a(9) =950745600a(10) =34459084800
External references
- oeis: A239840