Number of hierarchies of hierarchies of hierarchies on n points.
A075756
Number of hierarchies of hierarchies of hierarchies on n points.
Terms
- a(0) =1a(1) =1a(2) =6a(3) =52a(4) =588a(5) =8174a(6) =134537a(7) =2554647a(8) =54909468a(9) =1316675221a(10) =34820961457
External references
- oeis: A075756