OFFSET
1,1
COMMENTS
A string and its reverse are considered to be equivalent.
REFERENCES
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]
FORMULA
Sum mu(d)*A032121(n/d) where d|n.
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved