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A347091 Sum of A332844 and its Dirichlet inverse. 2
2, 0, 0, 9, 0, 24, 0, 21, 16, 36, 0, 28, 0, 48, 48, 37, 0, 36, 0, 42, 64, 72, 0, 60, 36, 84, 48, 56, 0, 0, 0, 81, 96, 108, 96, 114, 0, 120, 112, 90, 0, 0, 0, 84, 72, 144, 0, 164, 64, 84, 144, 98, 0, 120, 144, 120, 160, 180, 0, 216, 0, 192, 96, 166, 168, 0, 0, 126, 192, 0, 0, 258, 0, 228, 112, 140, 192, 0, 0, 246, 132 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
No negative terms in range 1 .. 2^20.
Apparently, A030059 gives the positions of all zeros.
LINKS
FORMULA
a(n) = A332844(n) + A347090(n).
For n > 1, a(n) = -Sum_{d|n, 1<d<n} A332844(d) * A347090(n/d).
For all n >= 1, a(A030059(n)) = 0, a(A030229(n)) = 2*A332844(A030229(n)).
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.
A332844(n) = sumdiv(n, d, issquare(n/d) * sigma(d));
v347090 = DirInverseCorrect(vector(up_to, n, A332844(n)));
A347090(n) = v347090[n];
A347091(n) = (A332844(n)+A347090(n));
CROSSREFS
Cf. also A347093.
Sequence in context: A323403 A346238 A347085 * A347229 A347095 A346255
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 18 2021
STATUS
approved

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Last modified May 17 09:50 EDT 2024. Contains 372579 sequences. (Running on oeis4.)