Squarefree part of lcm(1,...,n).

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =3a(5) =15a(6) =15a(7) =105a(8) =210a(9) =70a(10) =70a(11) =770a(12) =770a(13) =10010a(14) =10010a(15) =10010a(16) =5005a(17) =85085a(18) =85085a(19) =1616615a(20) =1616615a(21) =1616615a(22) =1616615a(23) =37182145a(24) =37182145a(25) =7436429a(26) =7436429a(27) =22309287a(28) =22309287a(29) =646969323