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A325633 a(n) = gcd(A009194(n), A325634(n)) = gcd(A009194(n), A091255(n, sigma(n))).

%I A325633 #8 May 21 2019 22:03:32
%S A325633 1,1,1,1,1,6,1,1,1,2,1,4,1,2,3,1,1,3,1,2,1,2,1,12,1,2,1,28,1,6,1,1,3,
%T A325633 2,1,1,1,2,1,10,1,2,1,4,1,2,1,4,1,1,3,2,1,2,1,8,1,2,1,4,1,2,1,1,1,6,1,
%U A325633 2,1,2,1,3,1,2,1,4,1,2,1,2,1,2,1,28,1,2,1,4,1,2,1,4,1,2,5,12,1,1,1,1,1,2,1,2,3
%N A325633 a(n) = gcd(A009194(n), A325634(n)) = gcd(A009194(n), A091255(n, sigma(n))).
%H A325633 Antti Karttunen, <a href="/A325633/b325633.txt">Table of n, a(n) for n = 1..65537</a>
%H A325633 <a href="/index/Ge#GF2X">Index entries for sequences related to polynomials in ring GF(2)[X]</a>
%H A325633 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A325633 a(n) = gcd(A009194(n), A325634(n)) = gcd(A009194(n), A091255(n, A000203(n))).
%o A325633 (PARI)
%o A325633 A009194(n) = gcd(n,sigma(n));
%o A325633 A091255sq(a,b) = fromdigits(Vec(lift(gcd(Pol(binary(a))*Mod(1, 2),Pol(binary(b))*Mod(1, 2)))),2);
%o A325633 A325634(n) = A091255sq(n, sigma(n));
%o A325633 A325633(n) = gcd(A009194(n),A325634(n));
%Y A325633 Cf. A000203, A091255, A325634.
%Y A325633 Differs from A009194 for the first time at n=42, where a(42) = 2, while A009194(42) = 6.
%Y A325633 Differs from A325632 and A325640 for the first time at n=45, where a(45) = 1, while A325632(45) = 5 and A325640(45) = 3.
%K A325633 nonn
%O A325633 1,6
%A A325633 _Antti Karttunen_, May 21 2019