a(n) = n! * (number of mapping patterns on n).

A254529

a(n) = n! * (number of mapping patterns on n).

Terms

    a(0) =1a(1) =1a(2) =6a(3) =42a(4) =456a(5) =5640a(6) =93600a(7) =1728720a(8) =38344320a(9) =948931200a(10) =26555558400a(11) =817935148800

External references