OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..65537
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} (1+A003415(n/d)) * a(d).
PROG
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Jan 13 2023
STATUS
approved