A305814 a(n) = Product_{d|n, d>1} prime(A305788(d)-1).
1, 2, 2, 6, 3, 20, 2, 42, 10, 66, 2, 660, 2, 20, 42, 546, 13, 1700, 2, 3762, 12, 20, 5, 106260, 6, 20, 110, 660, 5, 106260, 2, 15834, 20, 806, 30, 2075700, 2, 20, 44, 1079694, 2, 6600, 5, 660, 4830, 170, 2, 42822780, 10, 660, 754, 660, 5, 691900, 12, 106260, 44, 170, 2, 2731625820, 2, 20, 660, 680862, 114, 17000, 2, 113646, 30, 56100, 5
Offset: 1