Palindromic in bases 11 and 13.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =7a(8) =8a(9) =9a(10) =10a(11) =12a(12) =84a(13) =366a(14) =510a(15) =732a(16) =876a(17) =1020a(18) =1098a(19) =1242a(20) =1464a(21) =10248a(22) =30252a(23) =31110a(24) =62220a(25) =103704a(26) =146541a(27) =3382050a(28) =3698730a(29) =4391268