OFFSET
1,3
LINKS
FORMULA
PROG
(PARI)
up_to = 20000;
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.
A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};
v349348 = DirInverseCorrect(vector(up_to, n, A252463(n)));
A349348(n) = v349348[n];
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 15 2021
STATUS
approved