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a(n) = gcd(n-A048250(n), n-A162296(n)).
18

%I #6 Apr 24 2019 19:46:03

%S 1,1,1,1,1,6,1,1,5,2,1,4,1,2,3,1,1,3,1,2,1,2,1,12,19,2,1,4,1,6,1,1,3,

%T 2,1,1,1,2,1,2,1,6,1,4,3,2,1,4,41,1,3,2,1,6,1,8,1,2,1,12,1,2,1,1,1,6,

%U 1,2,3,2,1,3,1,2,1,4,1,6,1,2,1,2,1,4,1,2,3,4,1,18,7,4,1,2,5,12,1,1,3,1,1,6,1,2,3

%N a(n) = gcd(n-A048250(n), n-A162296(n)).

%H Antti Karttunen, <a href="/A325385/b325385.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = gcd(n-A048250(n), n-A162296(n)).

%F a(n) = gcd(A325313(n), A325314(n)).

%F a(A228058(n)) = A325375(n).

%o (PARI)

%o A048250(n) = factorback(apply(p -> p+1,factor(n)[,1]));

%o A162296(n) = sumdiv(n, d, d*(1-issquarefree(d)));

%o A325385(n) = gcd(n-A048250(n),n-A162296(n));

%Y Cf. A048250, A126795, A162296, A228058, A325313, A325314, A325375.

%K nonn

%O 1,6

%A _Antti Karttunen_, Apr 24 2019