%I #8 May 21 2019 22:03:39

%S 1,1,2,1,2,12,2,1,1,2,2,4,2,4,6,1,2,3,2,2,2,4,2,12,1,2,2,56,2,12,2,1,

%T 6,2,2,1,2,4,2,10,2,12,2,4,6,4,2,4,1,1,6,2,2,12,2,8,2,2,2,24,2,4,2,1,

%U 2,12,2,2,6,4,2,3,2,2,2,4,2,12,2,2,1,2,2,56,2,4,6,4,2,18,14,8,2,4,10,12,2,1,6,1,2,12,2,2,6

%N a(n) = gcd(2n, sigma(n)).

%H Antti Karttunen, <a href="/A325636/b325636.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = gcd(2n, A000203(n)).

%F a(n) = gcd(2n, A033879(n)) = gcd(sigma(n), A033879(n)).

%o (PARI) A325636(n) = gcd(n+n,sigma(n));

%Y Cf. A000203, A009194, A033879, A325385, A325635, A325637 (n such that a(n) = 2n).

%K nonn

%O 1,3

%A _Antti Karttunen_, May 21 2019