Palindromic odd squarefree numbers with an even number of distinct prime factors.

Terms

a(0) =1a(1) =33a(2) =55a(3) =77a(4) =111a(5) =141a(6) =161a(7) =303a(8) =323a(9) =393a(10) =505a(11) =515a(12) =535a(13) =545a(14) =565a(15) =707a(16) =717a(17) =737a(18) =767a(19) =939a(20) =949a(21) =959a(22) =979a(23) =989a(24) =1111a(25) =1441a(26) =1661a(27) =1991a(28) =3003a(29) =3113