Squarefree composite palindromes.

Terms

a(0) =6a(1) =22a(2) =33a(3) =55a(4) =66a(5) =77a(6) =111a(7) =141a(8) =161a(9) =202a(10) =222a(11) =262a(12) =282a(13) =303a(14) =323a(15) =393a(16) =434a(17) =454a(18) =474a(19) =494a(20) =505a(21) =515a(22) =535a(23) =545a(24) =555a(25) =565a(26) =595a(27) =606a(28) =626a(29) =646