Squares which have one or more occurrences of exactly two different digits.

Terms

a(0) =16a(1) =25a(2) =36a(3) =49a(4) =64a(5) =81a(6) =100a(7) =121a(8) =144a(9) =225a(10) =400a(11) =441a(12) =484a(13) =676a(14) =900a(15) =1444a(16) =7744a(17) =10000a(18) =11881a(19) =29929a(20) =40000a(21) =44944a(22) =55225a(23) =69696a(24) =90000a(25) =1000000a(26) =4000000a(27) =9000000a(28) =9696996a(29) =100000000