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%I #12 Sep 29 2019 11:09:51
%S 0,0,0,0,0,0,0,60,120,960,1800,9300,16800,71400,126000,480000,834120,
%T 2968440,5103000,17354340,29607600,97566000,165528000,533264700,
%U 901020120,2854995360,4809004080,15050445900,25292030400,78417321240,131542866000,404936052000
%N Number of primitive (period n) periodic palindromes using 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]
%H Andrew Howroyd, <a href="/A056501/b056501.txt">Table of n, a(n) for n = 1..200</a>
%F a(n) = Sum_{d|n} mu(d)*A056491(n/d).
%e For example, aaabbb is not a (finite) palindrome but it is a periodic palindrome.
%Y Column 5 of A327878.
%Y Cf. A056466, A056491.
%K nonn
%O 1,8
%A _Marks R. Nester_
%E Terms corrected by _Andrew Howroyd_, Sep 28 2019