Number of length n 0..4 arrays connected end-around, with no sequence of L<n elements immediately followed by itself ("periodic squarefree"), and new values introduced in order 0..4.
A215397
Number of length n 0..4 arrays connected end-around, with no sequence of L<n elements immediately followed by itself ("periodic squarefree"), and new values introduced in order 0..4.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =3a(4) =6a(5) =26a(6) =84a(7) =324a(8) =1170a(9) =4412a(10) =16313a(11) =61138a(12) =227383a(13) =849667a(14) =3168419a(15) =11831104a(16) =44144206a(17) =164792736a(18) =615027929a(19) =2295714687
External references
- oeis: A215397