a(n) = Product_{k>=1} floor(n^(1/k)).

Terms

a(0) =1a(1) =2a(2) =3a(3) =8a(4) =10a(5) =12a(6) =14a(7) =32a(8) =54a(9) =60a(10) =66a(11) =72a(12) =78a(13) =84a(14) =90a(15) =256a(16) =272a(17) =288a(18) =304a(19) =320a(20) =336a(21) =352a(22) =368a(23) =384a(24) =500a(25) =520a(26) =810a(27) =840a(28) =870a(29) =900