Number of binary necklaces of length n with no subsequence 00, excluding the necklace "0".

Terms

a(0) =1a(1) =2a(2) =2a(3) =3a(4) =3a(5) =5a(6) =5a(7) =8a(8) =10a(9) =15a(10) =19a(11) =31a(12) =41a(13) =64a(14) =94a(15) =143a(16) =211a(17) =329a(18) =493a(19) =766a(20) =1170a(21) =1811a(22) =2787a(23) =4341a(24) =6713a(25) =10462a(26) =16274a(27) =25415a(28) =39651a(29) =62075