Number of equivalence classes of length n squarefree reduced words over {0, 1, 2, 3} under action of renaming symbols.

A343484

Number of equivalence classes of length n squarefree reduced words over {0, 1, 2, 3} under action of renaming symbols.

Terms

    a(0) =0a(1) =1a(2) =1a(3) =2a(4) =3a(5) =5a(6) =8a(7) =13a(8) =18a(9) =27a(10) =41a(11) =62a(12) =90a(13) =134a(14) =198a(15) =293a(16) =423a(17) =619a(18) =908a(19) =1329a(20) =1938a(21) =2832a(22) =4142a(23) =6061a(24) =8824a(25) =12879a(26) =18794a(27) =27425a(28) =39977a(29) =58333

External references