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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.

A349373 Dirichlet convolution of Kimberling's paraphrases (A003602) with Dirichlet inverse of Euler phi (A023900).

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%I A349373 #10 Nov 21 2021 10:17:15
%S A349373 1,0,0,-1,-1,0,-2,-2,-1,0,-4,0,-5,0,2,-3,-7,0,-8,1,3,0,-10,0,-3,0,-2,
%T A349373 2,-13,0,-14,-4,5,0,8,1,-17,0,6,2,-19,0,-20,4,5,0,-22,0,-5,0,8,5,-25,
%U A349373 0,14,4,9,0,-28,-2,-29,0,8,-5,17,0,-32,7,11,0,-34,2,-35,0,4,8,23,0,-38,3,-3,0,-40,-3,23,0,14,8
%N A349373 Dirichlet convolution of Kimberling's paraphrases (A003602) with Dirichlet inverse of Euler phi (A023900).
%H A349373 Antti Karttunen, <a href="/A349373/b349373.txt">Table of n, a(n) for n = 1..20000</a>
%F A349373 a(n) = Sum_{d|n} A003602(n/d) * A023900(d).
%t A349373 f[p_, e_] := (1 - p); d[1] = 1; d[n_] := Times @@ f @@@ FactorInteger[n]; k[n_] := (n / 2^IntegerExponent[n, 2] + 1)/2; a[n_] := DivisorSum[n, k[#] * d[n/#] &]; Array[a, 100] (* _Amiram Eldar_, Nov 16 2021 *)
%o A349373 (PARI)
%o A349373 A003602(n) = (1+(n>>valuation(n,2)))/2;
%o A349373 A023900(n) = factorback(apply(p -> 1-p, factor(n)[, 1]));
%o A349373 A349373(n) = sumdiv(n,d,A003602(n/d)*A023900(d));
%Y A349373 Cf. A003602, A023900.
%Y A349373 Cf. A347954, A347955, A347956, A349136, A349370, A349371, A349372, A349374, A349375, A349390, A349431, A349444, A349447 for Dirichlet convolutions of other sequences with A003602.
%K A349373 sign
%O A349373 1,7
%A A349373 _Antti Karttunen_, Nov 15 2021