OFFSET
1,2
LINKS
FORMULA
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.
A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
v346234 = DirInverseCorrect(vector(up_to, n, A003961(n)));
A346234(n) = v346234[n];
(PARI)
A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
(PARI) A346234(n) = { my(f = factor(n)); prod(i=1, #f~, if(1<f[i, 2], 0, -nextprime(1+f[i, 1]))); }; \\ Antti Karttunen, Nov 14 2021
CROSSREFS
KEYWORD
sign,mult
AUTHOR
Antti Karttunen, Jul 11 2021
EXTENSIONS
Keyword:mult added by Antti Karttunen, Nov 14 2021
STATUS
approved