Number of ordered pairs of permutation functions on n elements satisfying f(f(x)) = g(f(g(x))).
A239837
Number of ordered pairs of permutation functions on n elements satisfying f(f(x)) = g(f(g(x))).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =12a(4) =96a(5) =600a(6) =6480a(7) =85680a(8) =1048320a(9) =16692480a(10) =315705600a(11) =5468601600a(12) =117834393600
External references
- oeis: A239837