login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A056282 Number of primitive (aperiodic) word structures of length n which contain exactly six different symbols. 1

%I #16 Apr 15 2021 21:40:49

%S 0,0,0,0,0,1,21,266,2646,22827,179487,1323651,9321312,63436352,

%T 420693273,2734926292,17505749898,110687248392,693081601779,

%U 4306078872557,26585679462783,163305339165738,998969857983405

%N Number of primitive (aperiodic) word structures of length n which contain exactly six different symbols.

%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 a(n) = Sum_{n > 0, d|n} mu(d)*A000770(n/d).

%F G.f.: Sum_{k>=1} mu(k) * x^(6*k) / Product_{j=1..6} (1 - j*x^k). - _Ilya Gutkovskiy_, Apr 15 2021

%Y Column 6 of A137651.

%Y Cf. A056271.

%K nonn

%O 1,7

%A _Marks R. Nester_

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 06:57 EDT 2024. Contains 371265 sequences. (Running on oeis4.)