Squares using only squarefree digits (2, 3, 5, 6, 7).

Terms

a(0) =25a(1) =36a(2) =225a(3) =256a(4) =576a(5) =625a(6) =676a(7) =5625a(8) =5776a(9) =7225a(10) =27225a(11) =27556a(12) =37636a(13) =55225a(14) =65536a(15) =75625a(16) =225625a(17) =226576a(18) =235225a(19) =265225a(20) =266256a(21) =275625a(22) =276676a(23) =367236a(24) =525625a(25) =553536a(26) =732736a(27) =765625a(28) =767376a(29) =2322576