Trimorphic but not bimorphic nor automorphic.

Terms

a(0) =4a(1) =9a(2) =24a(3) =49a(4) =51a(5) =75a(6) =99a(7) =125a(8) =249a(9) =251a(10) =375a(11) =499a(12) =501a(13) =624a(14) =749a(15) =751a(16) =875a(17) =999a(18) =1249a(19) =3751a(20) =4375a(21) =4999a(22) =5001a(23) =5625a(24) =6249a(25) =8751a(26) =9375a(27) =9999a(28) =18751a(29) =31249