%I #6 Aug 22 2017 20:53:12

%S 0,0,0,0,0,1,1,18,59,630,1681,28866,60083,757576,3514504,21423984,

%T 64372109,1024999170,2026631203,26920954613,105501588414,742299897060,

%U 1974251382095,31721456288956,74052852505684

%N Number of primitive (period n) step cyclic shifted sequence structures using exactly 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 A056443(n)-A056442(n).

%Y Cf. A056428.

%K nonn

%O 1,8

%A _Marks R. Nester_