For example, aaabbb is not a (finite) palindrome but it is a periodic palindrome. Permuting the symbols will not change the structure.
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]
Table of n, a(n) for n=1..15.
Sum mu(d)*A056507(n/d) where d|n.
Sequence in context: A121720 A056515 A056516 * A285042 A319719 A048155
Adjacent sequences: A056514 A056515 A056516 * A056518 A056519 A056520
Marks R. Nester
Corrected by T. D. Noe, Oct 25 2006