|
%I #6 Aug 22 2017 20:53:07
%S 1,1,4,13,51,197,875,4096,20643,109246,601491,3402911,19628063,
%T 114699438,676207572,4010086352,23874362199,142508702805,852124263683,
%U 5101098123207,30560194492576,183176169456214
%N Number of primitive (aperiodic) word structures of length n using a 6-ary alphabet.
%C Permuting the alphabet will not change a word structure. Thus aabc and bbca have the same structure.
%D M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia. [See A056391 for pdf file of Chap. 2]
%F sum mu(d)*A056273(n/d) where d|n and n>0.
%Y Cf. A054721.
%K nonn
%O 1,3
%A _Marks R. Nester_
|
