OFFSET
1,3
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537
PROG
(PARI)
up_to = 65537;
A063994(n) = { my(f=factor(n)); prod(i=1, #f~, gcd(f[i, 1]-1, n-1)); };
DirInverse(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = -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.
v340187 = DirInverse(vector(up_to, n, A063994(n)));
A340187(n) = v340187[n];
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Dec 31 2020
STATUS
approved