%I #6 Aug 22 2017 20:53:12
%S 1,1,2,5,7,33,35,212,449,2991,5651,74919,126757,1370979,5653844,
%T 31440622,87796361,1319721998,2491714133,31893714060,121274777190,
%U 832622957033,2170594048581,34308978905916
%N Number of primitive (period n) step cyclic shifted sequence structures using a maximum of six different symbols.
%C See A056371 for an explanation of step shifts. Under step cyclic shifts, abcde, bdace, bcdea, cdeab and daceb etc. are equivalent. Permuting the symbols will not change the 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)*A056433(n/d) where d|n.
%Y Cf. A056423.
%K nonn
%O 1,3
%A _Marks R. Nester_