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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A347084 Dirichlet inverse of A129283, n + A003415(n).

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%I A347084 #11 Nov 15 2021 01:32:00
%S A347084 1,-3,-4,1,-6,13,-8,1,1,19,-12,-6,-14,25,25,1,-18,-5,-20,-8,33,37,-24,
%T A347084 -5,1,43,2,-10,-30,-87,-32,1,49,55,49,6,-38,61,57,-7,-42,-113,-44,-14,
%U A347084 -8,73,-48,-4,1,-5,73,-16,-54,-9,73,-9,81,91,-60,51,-62,97,-10,1,85,-165,-68,-20,97,-163,-72,2,-74,115
%N A347084 Dirichlet inverse of A129283, n + A003415(n).
%H A347084 Antti Karttunen, <a href="/A347084/b347084.txt">Table of n, a(n) for n = 1..16384</a>
%F A347084 a(1) = 1; and for n > 2, a(n) = -Sum_{d|n, d<n} a(d) * A129283(n/d).
%F A347084 a(n) = A347085(n) - A129283(n).
%F A347084 a(n) = A347082(n) - A347086(n).
%o A347084 (PARI)
%o A347084 up_to = 16384;
%o A347084 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.
%o A347084 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A347084 v347084 = DirInverseCorrect(vector(up_to,n,n+A003415(n)));
%o A347084 A347084(n) = v347084[n];
%Y A347084 Cf. A003415, A129283, A347082, A347085, A347086, A348995 (positions of 1's).
%Y A347084 Cf. also A346241, A348976.
%K A347084 sign
%O A347084 1,2
%A A347084 _Antti Karttunen_, Aug 17 2021