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a(1) = gcd((sigma(n)-A032742(n))-n, n-A032742(n)), where A032742 gives the largest proper divisor of n.
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%I #9 Jun 06 2019 21:59:28

%S 1,1,2,1,4,3,6,1,1,1,10,2,12,1,2,1,16,3,18,2,2,1,22,12,1,1,2,14,28,3,

%T 30,1,2,1,2,1,36,1,2,10,40,3,42,2,6,1,46,4,1,1,2,2,52,3,2,4,2,1,58,6,

%U 60,1,2,1,2,3,66,2,2,1,70,3,72,1,2,2,2,3,78,2,1,1,82,14,2,1,2,4,88,9,2,2,2,1,2,12,96,1,6,1,100,3,102,2,2

%N a(1) = gcd((sigma(n)-A032742(n))-n, n-A032742(n)), where A032742 gives the largest proper divisor of n.

%C See comments in A326063 and A326064.

%H Antti Karttunen, <a href="/A326062/b326062.txt">Table of n, a(n) for n = 1..20000</a>

%F a(1) = 1; for n > 1, a(n) = gcd(A060681(n), A318505(n)).

%F a(n) = gcd((A000203(n)-A032742(n))-n, n-A032742(n)).

%o (PARI)

%o A032742(n) = if(1==n,n,n/vecmin(factor(n)[,1]));

%o A326062(n) = gcd((sigma(n)-A032742(n))-n, n-A032742(n));

%Y Cf. A000203, A032742, A060681, A318505, A326061, A326063, A326064.

%Y Cf. also A009194, A325385, A325813, A325975, A326046, A326047, A326048, A326056, A326057, A326060.

%K nonn

%O 1,3

%A _Antti Karttunen_, Jun 06 2019