Palindromic in bases 7 and 10.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =8a(8) =121a(9) =171a(10) =242a(11) =292a(12) =16561a(13) =65656a(14) =2137312a(15) =4602064a(16) =6597956a(17) =6958596a(18) =9470749a(19) =61255216a(20) =230474032a(21) =466828664a(22) =485494584a(23) =638828836a(24) =657494756a(25) =858474858a(26) =25699499652a(27) =40130703104a(28) =45862226854