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a(n) = +1 if n > phi(sigma(n)), -1 if n < phi(sigma(n)), and 0 if n = phi(sigma(n)), where phi = A000010 and sigma = A000203.
5

%I #6 Nov 21 2017 21:36:34

%S 0,0,1,-1,1,1,1,0,-1,1,1,0,1,1,1,-1,1,-1,1,1,1,1,1,1,-1,1,1,1,1,1,1,

%T -1,1,1,1,-1,1,1,1,1,1,1,1,1,1,1,1,-1,1,-1,1,1,1,1,1,1,1,1,1,1,1,1,1,

%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

%N a(n) = +1 if n > phi(sigma(n)), -1 if n < phi(sigma(n)), and 0 if n = phi(sigma(n)), where phi = A000010 and sigma = A000203.

%H Antti Karttunen, <a href="/A295303/b295303.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = sign(A295301(n)) = sign(n - phi(sigma(n))).

%o (PARI) A295303(n) = sign(n - eulerphi(sigma(n)));

%Y Cf. A000010, A000203, A062401, A295301, A295304.

%Y Cf. A001229 (positions of 0's), A066694 (of -1's).

%K sign

%O 1

%A _Antti Karttunen_, Nov 21 2017