a(n) = n^(n-2) * (n-1)^(n-1).A070285a(n) = n^(n-2) * (n-1)^(n-1).Terms a(0) =1a(1) =12a(2) =432a(3) =32000a(4) =4050000a(5) =784147392a(6) =215886856192External referencesoeis: A070285