Smallest number whose square is divisible by n!.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =12a(5) =60a(6) =60a(7) =420a(8) =1680a(9) =5040a(10) =5040a(11) =55440a(12) =332640a(13) =4324320a(14) =8648640a(15) =43243200a(16) =172972800a(17) =2940537600a(18) =8821612800a(19) =167610643200a(20) =335221286400