%I
%S 1,1,2,5,10,35,102,360,1232,4427,15934,58465,215250,799593,2983204,
%T 11187200,42109450,159081482,602809326,2290679807,8726308212,
%U 33318645341,127479700198,488672244040,1876500180280
%N Number of primitive (period n) nbead necklace structures using a maximum of four different colored beads.
%C Turning over the necklace is not allowed. Colors may be permuted without changing the necklace 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_{dn} mu(d) * A056292(n/d); mu = A008683.
%Y Cf. A008683, A027377, A056292.
%K nonn
%O 1,3
%A _Marks R. Nester_
