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%I #7 Jun 12 2019 19:14:00
%S 1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,27,1,1,1,1,1,1,
%T 1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,7,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%U 1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,5,1,1,1,1,5,1,1,1,7,5,1,1,1,1,1,1,1,1,1
%N a(n) = gcd(1+n-A020639(n), 1+sigma(n)-A020639(n)-n), where A020639 gives the smallest prime factor of n (and 1 for 1), and sigma is the sum of divisors of n.
%H Antti Karttunen, <a href="/A326073/b326073.txt">Table of n, a(n) for n = 1..65537</a>
%F a(n) = gcd(1+n-A020639(n), 1+A000203(n)-A020639(n)-n).
%o (PARI)
%o A020639(n) = if(1==n, n, factor(n)[1, 1]);
%o A326073(n) = gcd(1+n-A020639(n), 1+sigma(n)-A020639(n)-n);
%Y Cf. A000203, A020639, A326074.
%Y Cf. also A009194, A325385, A325813, A325975, A326046, A326047, A326048, A326056, A326057, A326060, A326062, A326129, A326130, A326140, A326144, A326147.
%K nonn
%O 1,6
%A _Antti Karttunen_, Jun 10 2019