Number of primitive (aperiodic) palindromic structures of length n using an infinite alphabet.

Terms

a(0) =1a(1) =0a(2) =1a(3) =1a(4) =4a(5) =3a(6) =14a(7) =13a(8) =50a(9) =47a(10) =202a(11) =197a(12) =876a(13) =862a(14) =4134a(15) =4125a(16) =21146a(17) =21092a(18) =115974a(19) =115922a(20) =678554a(21) =678367a(22) =4213596a(23) =4213381a(24) =27644432a(25) =27643560a(26) =190899270a(27) =190898444a(28) =1382958544a(29) =1382954355