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A326048 a(n) = gcd(n-A050449(n), A082052(n)-n), where A050449 and A082052 give the sum of divisors of the form 4k+1, and not of that form, respectively.

%I A326048 #9 Jun 04 2019 16:32:59
%S A326048 1,1,2,1,1,5,6,1,1,2,10,1,1,1,3,1,1,1,18,2,1,1,22,1,1,2,1,27,1,12,30,
%T A326048 1,1,2,1,1,1,1,1,2,1,4,42,1,3,5,46,1,1,1,3,2,1,4,1,1,1,2,58,6,1,1,2,1,
%U A326048 1,4,66,10,1,4,70,1,1,2,2,3,1,4,78,2,1,2,82,2,1,5,3,1,1,6,7,1,1,1,1,5,1,1,14,1,1,12,102,2,9
%N A326048 a(n) = gcd(n-A050449(n), A082052(n)-n), where A050449 and A082052 give the sum of divisors of the form 4k+1, and not of that form, respectively.
%H A326048 Antti Karttunen, <a href="/A326048/b326048.txt">Table of n, a(n) for n = 1..20000</a>
%F A326048 a(n) = gcd(A326049(n), A326050(n)) = gcd(n-A050449(n), A082052(n)-n).
%F A326048 a(2n-1) = A326047(2n-1) for all n.
%o A326048 (PARI)
%o A326048 A050449(n) = sumdiv(n, d, d*((d % 4) == 1)); \\ From A050449
%o A326048 A326049(n) = (n-A050449(n));
%o A326048 A082052(n) = sumdiv(n, d, if(1!=(d%4), d));
%o A326048 A326050(n) = (A082052(n)-n);
%o A326048 A326048(n) = gcd(A326049(n), A326050(n));
%Y A326048 Cf. A050449, A082052, A326047, A326049, A326050.
%Y A326048 Cf. also A009194, A325385, A325813, A325975.
%K A326048 nonn
%O A326048 1,3
%A A326048 _Antti Karttunen_, Jun 04 2019