Palindromic in base 7.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =8a(8) =16a(9) =24a(10) =32a(11) =40a(12) =48a(13) =50a(14) =57a(15) =64a(16) =71a(17) =78a(18) =85a(19) =92a(20) =100a(21) =107a(22) =114a(23) =121a(24) =128a(25) =135a(26) =142a(27) =150a(28) =157a(29) =164