Palindromic even numbers with an odd number of prime factors (counted with multiplicity).

Terms

a(0) =2a(1) =8a(2) =44a(3) =66a(4) =212a(5) =222a(6) =242a(7) =252a(8) =272a(9) =282a(10) =292a(11) =404a(12) =434a(13) =464a(14) =474a(15) =494a(16) =606a(17) =616a(18) =646a(19) =656a(20) =696a(21) =828a(22) =848a(23) =888a(24) =2222a(25) =2552a(26) =2882a(27) =4004a(28) =4224a(29) =4334