%I #9 Feb 07 2025 05:36:24
%S 0,-1,0,-1,1,-1,1,-1,1,-1,1,-1,1,-1,0,-1,1,-1,1,-1,1,-1,1,-1,1,1,1,0,
%T 1,-1,1,-1,1,-1,1,-1,1,1,1,-1,1,-1,1,-1,1,-1,1,-1,1,-1,1,1,1,-1,1,1,1,
%U -1,1,-1,1,1,1,-1,1,-1,1,-1,1,-1,1,-1,1,1,1,1,1,-1,1,-1,1,1,1,-1,1,1,1,1,1,-1,1,-1,1,-1,1,-1,1,-1,1,-1,1,-1,1,1,1
%N a(n) = +1 if sigma(phi(n)) > n, -1 if sigma(phi(n)) < n, and 0 if sigma(phi(n)) = n, where phi = A000010 and sigma = A000203.
%H Antti Karttunen, <a href="/A295304/b295304.txt">Table of n, a(n) for n = 1..65537</a>
%F a(n) = sign(A295302(n)) = sign(sigma(phi(n))-n), where phi = A000010 and sigma = A000203.
%t Array[Sign[DivisorSigma[1, EulerPhi[#]] - #] &, 100] (* _Paolo Xausa_, Feb 07 2025 *)
%o (PARI) A295304(n) = sign(sigma(eulerphi(n)) - n);
%Y Cf. A000010, A000203, A062402, A295302, A295303
%Y Cf. A018784 (positions of 0's), A230201 (of -1's), A230203 (of +1's).
%K sign
%O 1
%A _Antti Karttunen_, Nov 21 2017