%I
%S 0,0,3,21,39,285,309,1638,3099,14109,17157,135918,130995,789819,
%T 1791447,5425938,8047839,64463793,64486017,437310162,871626729,
%U 3136882659,4278115101,35355495078,42359479599
%N Number of primitive (aperiodic) step shifted (decimated) sequences using exactly three different symbols.
%C See A056371 for an explanation of step shifts.
%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)*A056377(n/d) where dn.
%K nonn
%O 1,3
%A _Marks R. Nester_
