Number of different strings of length n obtained from "abcdefgh" by iteratively duplicating any substring.

A137748

Number of different strings of length n obtained from "abcdefgh" by iteratively duplicating any substring.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =1a(9) =8a(10) =43a(11) =196a(12) =814a(13) =3188a(14) =12018a(15) =44178a(16) =159660a(17) =570262a(18) =2019964a(19) =7112774a(20) =24940259a(21) =87191430a(22) =304203350a(23) =1059928798a(24) =3690123329a(25) =12841859908a(26) =44685411866a(27) =155506929954a(28) =541315997526

External references