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A354348
Dirichlet inverse of function f(1) = 1, f(n) = gcd(A003415(n), A276086(n)) for n > 1.
8
1, -1, -1, 0, -1, -3, -1, -2, -5, 1, -1, 8, -1, -1, 0, 4, -1, 18, -1, -2, -8, 1, -1, 0, -9, -13, 8, 4, -1, 9, -1, -2, -12, 1, -4, -9, -1, -19, 0, 8, -1, 29, -1, -2, 10, -23, -1, 2, -13, 4, -8, 22, -1, 20, 0, 2, 0, 1, -1, -13, -1, -1, 26, 2, -16, 33, -1, -2, 0, 13, -1, -14, -1, -1, 16, 36, -16, 37, -1, -10, 19, 1
OFFSET
1,6
LINKS
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A327858(n/d) * a(d).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A327858(n) = gcd(A003415(n), A276086(n));
memoA354348 = Map();
A354348(n) = if(1==n, 1, my(v); if(mapisdefined(memoA354348, n, &v), v, v = -sumdiv(n, d, if(d<n, A327858(n/d)*A354348(d), 0)); mapput(memoA354348, n, v); (v)));
CROSSREFS
Cf. also A346242, A354347.
Sequence in context: A138382 A123375 A021036 * A211025 A125704 A357498
KEYWORD
sign
AUTHOR
Antti Karttunen, Jun 08 2022
STATUS
approved