OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..16384
PROG
(PARI)
up_to = 16384;
DirInverseCorrect(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = (-u[1]*sumdiv(n, d, if(d<n, v[n/d]*u[d], 0)))); (u) }; \\ Compute the Dirichlet inverse of the sequence given in input vector v.
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
v347082 = DirInverseCorrect(vector(up_to, n, n-A003415(n)));
A347082(n) = v347082[n];
v347084 = DirInverseCorrect(vector(up_to, n, n+A003415(n)));
A347084(n) = v347084[n];
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Aug 17 2021
STATUS
approved