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A354186
Dirichlet inverse of A348717.
7
1, -2, -2, 0, -2, 2, -2, 0, 0, -2, -2, 4, -2, -6, 2, 0, -2, -2, -2, 12, -2, -14, -2, 0, 0, -18, 0, 20, -2, 10, -2, 0, -6, -26, 2, 8, -2, -30, -14, 0, -2, 30, -2, 36, 4, -38, -2, 0, 0, -18, -18, 44, -2, -6, -2, 0, -26, -50, -2, -4, -2, -54, 12, 0, -6, 54, -2, 60, -30, 2, -2, -8, -2, -66, -2, 68, 2, 90, -2, 0, 0, -74
OFFSET
1,2
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d < n} A348717(n/d) * a(d).
a(n) = A354187(n) - A348717(n).
PROG
(PARI)
A348717(n) = if(1==n, 1, my(f = factor(n), k = primepi(f[1, 1])-1); for (i=1, #f~, f[i, 1] = prime(primepi(f[i, 1])-k)); factorback(f));
memoA354186 = Map();
A354186(n) = if(1==n, 1, my(v); if(mapisdefined(memoA354186, n, &v), v, v = -sumdiv(n, d, if(d<n, A348717(n/d)*A354186(d), 0)); mapput(memoA354186, n, v); (v)));
CROSSREFS
Sequence in context: A029310 A348220 A134131 * A366265 A127527 A356583
KEYWORD
sign
AUTHOR
Antti Karttunen, May 19 2022
STATUS
approved