Number of 3-abelian equivalence classes of words of length n over a binary alphabet.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =16a(5) =32a(6) =60a(7) =106a(8) =176a(9) =280a(10) =426a(11) =626a(12) =892a(13) =1238a(14) =1678a(15) =2230a(16) =2910a(17) =3738a(18) =4734a(19) =5920a(20) =7318a(21) =8954a(22) =10852a(23) =13040a(24) =15546a(25) =18400a(26) =21632a(27) =25276a(28) =29364a(29) =33932