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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.

A349385 Dirichlet convolution of A048673 with the Dirichlet inverse of A003961, where A003961 is fully multiplicative with a(p) = nextprime(p), and A048673(n) = (1+A003961(n))/2.

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%I A349385 #13 Nov 26 2021 16:17:51
%S A349385 1,-1,-2,-1,-3,4,-5,-1,-2,6,-6,4,-8,10,12,-1,-9,4,-11,6,20,12,-14,4,
%T A349385 -3,16,-2,10,-15,-24,-18,-1,24,18,30,4,-20,22,32,6,-21,-40,-23,12,12,
%U A349385 28,-26,4,-5,6,36,16,-29,4,36,10,44,30,-30,-24,-33,36,20,-1,48,-48,-35,18,56,-60,-36,4,-39,40,12,22,60
%N A349385 Dirichlet convolution of A048673 with the Dirichlet inverse of A003961, where A003961 is fully multiplicative with a(p) = nextprime(p), and A048673(n) = (1+A003961(n))/2.
%C A349385 Convolving this with A003973 gives A336840.
%H A349385 Antti Karttunen, <a href="/A349385/b349385.txt">Table of n, a(n) for n = 1..20000</a>
%H A349385 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F A349385 a(n) = Sum_{d|n} A048673(n/d) * A346234(d).
%F A349385 a(n) = A349386(n) - A349384(n).
%o A349385 (PARI)
%o A349385 A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
%o A349385 A048673(n) = (A003961(n)+1)/2;
%o A349385 A346234(n) = (moebius(n)*A003961(n));
%o A349385 A349385(n) = sumdiv(n,d,A048673(n/d)*A346234(d));
%Y A349385 Cf. A003961, A048673, A346234, A349384 (Dirichlet inverse), A349386 (sum with it).
%Y A349385 Cf. also A003973, A336840.
%K A349385 sign
%O A349385 1,3
%A A349385 _Antti Karttunen_, Nov 17 2021