cp's OEIS Frontend

A353757 a(n) = A353750(n) - A353749(n).

%I A353757 #12 May 12 2022 16:12:57
%S A353757 0,3,-2,28,-8,4,-26,44,108,12,-62,52,-102,-14,-32,862,-184,504,-282,
%T A353757 96,-104,-22,-402,80,690,-12,-96,60,-596,48,-854,704,-248,-64,-328,
%U A353757 3912,-810,-210,-408,240,-1360,-56,-1582,100,240,-322,-1946,1708,174,3300,-736,786,-2300,48,-744,72,-1128,-356,-2978,384
%N A353757 a(n) = A353750(n) - A353749(n).
%C A353757 It is conjectured that there are no other zeros after a(1) = 0.
%H A353757 Antti Karttunen, <a href="/A353757/b353757.txt">Table of n, a(n) for n = 1..10000</a>
%H A353757 Antti Karttunen, <a href="/A353757/a353757.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%H A353757 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A353757 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A353757 a(n) = A353750(n) - A353749(n) = A353749(A000203(n)) - A353749(n).
%o A353757 (PARI)
%o A353757 A064989(n) = { my(f=factor(n>>valuation(n,2))); for(i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f); };
%o A353757 A353749(n) = (eulerphi(n)*A064989(n));
%o A353757 A353757(n) = { my(s=sigma(n)); (A353749(s)-A353749(n)); };
%Y A353757 Cf. A000203, A064989, A353749, A353750, A353758 (positions of negative terms), A353759 (of terms >= 0), A353760.
%Y A353757 Cf. also A348736.
%K A353757 sign
%O A353757 1,2
%A A353757 _Antti Karttunen_, May 10 2022