Number of pairs of functions f, g on a size n set into itself satisfying f(f(g(x))) = f(g(g(x))).
A239780
Number of pairs of functions f, g on a size n set into itself satisfying f(f(g(x))) = f(g(g(x))).
Terms
- a(0) =1a(1) =1a(2) =12a(3) =279a(4) =11128a(5) =669605a(6) =55937376a(7) =6146973259
External references
- oeis: A239780