Number of endofunctions on [2n] such that the image size equals n.
A288312
Number of endofunctions on [2n] such that the image size equals n.
Terms
- a(0) =1a(1) =2a(2) =84a(3) =10800a(4) =2857680a(5) =1285956000a(6) =880599202560
External references
- oeis: A288312