776736domain: NAppears in sequencesa(n) = Sum_{k=1..n} n! * n^(n-k+1) / (n-k)!.at n=6A036360a(n) = n*(n-1)*(n-3)*(n-5).at n=32A062765Balanced refactorable numbers.at n=27A078543Numbers n such that sigma(n) = 10*phi(n) (where sigma=A000203, phi=A000010).at n=31A171256