Internal digits of n^2 include digits of n.

Terms

a(0) =50a(1) =60a(2) =74a(3) =250a(4) =278a(5) =463a(6) =500a(7) =501a(8) =502a(9) =503a(10) =504a(11) =505a(12) =506a(13) =507a(14) =508a(15) =509a(16) =523a(17) =600a(18) =601a(19) =602a(20) =603a(21) =724a(22) =740a(23) =760a(24) =878a(25) =1050a(26) =1276a(27) =1390a(28) =1463a(29) =1523