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a(n) = sigma(phi(n)) - n, where phi = A000010 and sigma = A000203.
4

%I #10 Mar 27 2019 13:50:48

%S 0,-1,0,-1,2,-3,5,-1,3,-3,7,-5,15,-2,0,-1,14,-6,20,-5,7,-4,13,-9,17,2,

%T 12,0,27,-15,41,-1,9,-3,25,-8,54,1,21,-9,49,-14,53,-2,15,-10,25,-17,

%U 47,-8,12,8,45,-15,35,4,34,-2,31,-29,107,10,28,-1,59,-24,77,-5,15,-10,73,-12,122,17,15,15,91,-18,89,-17,39,8

%N a(n) = sigma(phi(n)) - n, where phi = A000010 and sigma = A000203.

%H Antti Karttunen, <a href="/A295302/b295302.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = A062402(n) - n.

%t Table[DivisorSigma[1,EulerPhi[n]]-n,{n,90}] (* _Harvey P. Dale_, Mar 27 2019 *)

%o (PARI) A295302(n) = (sigma(eulerphi(n)) - n);

%Y Cf. A000010, A000203, A062402, A295301, A295304.

%Y Cf. A018784 (positions of zeros), A230201 (of negative terms), A230203 (of positive terms).

%K sign

%O 1,5

%A _Antti Karttunen_, Nov 21 2017