OFFSET
0,2
LINKS
Eric Weisstein's World of Mathematics, Squarefree Word
FORMULA
a(n) = A006156(n)*2/3 for n>1 [Corrected by Rémy Sigrist, Aug 19 2020].
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 25 2003
STATUS
approved