Number of squarefree words of length n in a 6-ary alphabet, with new values 0..5 introduced in increasing order.

A215072

Number of squarefree words of length n in a 6-ary alphabet, with new values 0..5 introduced in increasing order.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =12a(5) =40a(6) =153a(7) =638a(8) =2825a(9) =12938a(10) =60458a(11) =285664a(12) =1358283a(13) =6480694a(14) =30979999a(15) =148249768a(16) =709832688a(17) =3399805736a(18) =16286469156a(19) =78026226228a(20) =373832145200

External references