%I #6 May 30 2019 09:43:53
%S 1,1,1,1,1,0,1,1,1,0,1,0,1,0,0,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,1,0,0,
%T 1,1,1,0,1,0,1,0,1,0,0,0,1,0,1,1,0,0,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,0,
%U 0,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,0,0,1,0,0,0,1,0,0,0,1,1,0,1,1,0,1,0,0
%N a(n) = 1 if n and sigma(n) are relatively prime, 0 otherwise, where sigma(n) = sum of divisors of n, A000203; Characteristic function of A014567.
%H Antti Karttunen, <a href="/A325964/b325964.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = 1 if gcd(n, sigma(n)) [= A009194(n)] is 1, 0 otherwise.
%o (PARI) A325964(n) = (1==gcd(n,sigma(n)));
%Y Cf. A000203, A009194, A014567.
%Y Cf. also A297086, A322980.
%K nonn
%O 1
%A _Antti Karttunen_, May 29 2019