%I #6 Aug 22 2017 20:53:07

%S 0,0,0,0,120,1800,16800,126000,834120,5102880,29607600,165526200,

%T 901020120,4808987400,25292030280,131542740000,678330198120,

%U 3474970629480,17710714165200,89904725757000

%N Number of primitive (aperiodic) words of length n which contain exactly five different symbols.

%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)*A001118(n/d) where d|n.

%Y Cf. A000351, A001118, A054720.

%K nonn

%O 1,5

%A _Marks R. Nester_