a(n) = Product_{k=0..n-1} n/gcd(n, A056040(k)).

Terms

a(0) =1a(1) =1a(2) =4a(3) =27a(4) =64a(5) =3125a(6) =108a(7) =823543a(8) =65536a(9) =14348907a(10) =12500a(11) =285311670611a(12) =746496a(14) =3294172a(15) =7119140625a(18) =1549681956a(20) =40000000000