%I #12 Sep 05 2018 17:18:57
%S 1,1,2,1,4,2,6,1,5,4,10,2,12,6,6,1,16,5,18,4,10,10,22,2,19,12,14,6,28,
%T 6,30,1,18,16,22,5,36,18,22,4,40,10,42,10,12,22,46,2,41,19,30,12,52,
%U 14,38,6,34,28,58,6,60,30,22,1,46,18,66,16,42,22,70,5,72,36,26,18,58,22,78,4,41,40,82,10,62,42,54,10,88,12,70,22,58,46,70,2
%N Sum of A083254(d) for all such divisors d of n for which A083254(d) > 0.
%H Antti Karttunen, <a href="/A318878/b318878.txt">Table of n, a(n) for n = 1..65537</a>
%F a(n) = Sum_{d|n} [A083254(d) > 0]*A083254(d), where A083254(n) = 2*phi(n) - n, and [ ] are the Iverson brackets.
%F a(n) = A318879(n) + A033879(n).
%e n = 105 has divisors [1, 3, 5, 7, 15, 21, 35, 105]. When A083254 is applied to them, we obtain [1, 1, 3, 5, 1, 3, 13, -9]. Summing the positive numbers present, we get a(105) = 1+1+3+5+1+3+13 = 27.
%o (PARI) A318878(n) = sumdiv(n,d,d=(2*eulerphi(d))-d; (d>0)*d);
%Y Cf. A000010, A033879, A083254, A318879.
%Y Cf. also A318678, A318874, A318876.
%K nonn
%O 1,3
%A _Antti Karttunen_, Sep 05 2018
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