a(n) = product of numbers k <= n such that not all proper divisors of k are divisors of n.

A158978

a(n) = product of numbers k <= n such that not all proper divisors of k are divisors of n.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =1a(6) =24a(7) =6a(8) =192a(9) =432a(10) =17280a(11) =10a(12) =207360a(13) =51840a(14) =322560a(15) =1360800a(16) =696729600a(17) =3225600a(18) =12541132800a(19) =39191040a(20) =27869184000a(23) =349272000

External references