a(n) is squarefree and sum of all squarefrees <= a(n) is squarefree.

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =6a(5) =10a(6) =13a(7) =15a(8) =19a(9) =22a(10) =26a(11) =30a(12) =31a(13) =35a(14) =38a(15) =39a(16) =41a(17) =43a(18) =51a(19) =55a(20) =59a(21) =65a(22) =66a(23) =67a(24) =69a(25) =70a(26) =73a(27) =74a(28) =78a(29) =79