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%I #9 Aug 22 2017 20:53:09
%S 0,0,0,0,0,1,12,142,1346,11511,89974,662673,4662574,31724723,
%T 210361046,1367510184,8752976610,55343946628,346541488998,
%U 2153041576027,13292844257186,81652683460145,499484958151630
%N Number of primitive (aperiodic) reversible string structures with n beads using exactly six different colors.
%C A string and its reverse are considered to be equivalent. Permuting the colors 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 A056335(n)-A056334(n).
%Y Column 6 of A276544.
%Y Cf. A056322.
%K nonn
%O 1,7
%A _Marks R. Nester_