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A349398
Dirichlet convolution of A048673 with the Dirichlet inverse of its inverse permutation.
9
1, 0, 0, 0, 0, 1, -5, 8, 0, -6, -3, 2, 0, 19, -5, -4, -4, 20, -19, 22, 6, -15, 3, -8, 0, 0, 16, 16, -18, 24, -40, 70, 9, -24, 21, -7, -50, 55, 8, -24, 6, -41, -15, 58, 20, -17, -31, 108, 27, 70, -37, -24, 0, -20, -49, -98, 6, 26, -13, 21, -15, 62, 158, 84, -22, 9, -49, 130, -67, 12, -49, 62, -29, 112, 4, -60, 103, 16
OFFSET
1,7
COMMENTS
Dirichlet convolution of A048673 with A349358, which is the Dirichlet inverse of A064216 (inverse permutation of A048673). Therefore, convolving A064216 with this sequence gives A048673.
Note how for n = 1 .. 35, a(n) = -A349397(n).
FORMULA
a(n) = Sum_{d|n} A048673(n/d) * A349358(d).
PROG
(PARI)
A048673(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); (1/2)*(1+factorback(f)); };
A064216(n) = { my(f = factor(n+n-1)); 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); };
memoA349358 = Map();
A349358(n) = if(1==n, 1, my(v); if(mapisdefined(memoA349358, n, &v), v, v = -sumdiv(n, d, if(d<n, A064216(n/d)*A349358(d), 0)); mapput(memoA349358, n, v); (v)));
A349398(n) = sumdiv(n, d, A048673(n/d)*A349358(d));
CROSSREFS
Cf. A003961, A048673, A064216, A064989, A323893, A349397 (Dirichlet inverse), A349399 (sum with it).
Cf. also A349376, A349377, A349385.
Sequence in context: A153420 A193505 A141848 * A349397 A140249 A335928
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 19 2021
STATUS
approved