The radical of the swinging factorial A056040.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =6a(5) =30a(6) =10a(7) =70a(8) =70a(9) =210a(10) =42a(11) =462a(12) =462a(13) =6006a(14) =858a(15) =4290a(16) =4290a(17) =72930a(18) =24310a(19) =461890a(20) =92378a(21) =1939938a(22) =176358a(23) =4056234a(24) =1352078a(25) =6760390a(26) =520030a(27) =1560090a(28) =222870a(29) =6463230