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a(n) = A353749(n) / gcd(A353749(n), A353750(n)).
5

%I #10 May 12 2022 16:13:18

%S 1,1,2,1,3,1,15,1,2,1,35,2,22,15,3,4,26,1,51,1,15,35,209,1,6,11,3,1,

%T 161,1,435,1,35,13,45,2,62,51,22,1,37,15,123,7,6,209,989,8,175,3,26,

%U 44,611,3,35,5,51,161,1537,1,118,435,15,16,33,35,2013,26,209,15,2345,1,142,31,12,17,525,11,949,4,432

%N a(n) = A353749(n) / gcd(A353749(n), A353750(n)).

%C Numerator of ratio A353749(n) / A353750(n).

%H Antti Karttunen, <a href="/A353762/b353762.txt">Table of n, a(n) for n = 1..10000</a>

%H Antti Karttunen, <a href="/A353762/a353762.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = A353749(n) / A353761(n) = A353749(n) / gcd(A353749(n), A353750(n)).

%o (PARI)

%o A064989(n) = { my(f=factor(n>>valuation(n,2))); for(i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f); };

%o A353749(n) = (eulerphi(n)*A064989(n));

%o A353762(n) = { my(s=sigma(n), u=A353749(n)); (u / gcd(A353749(s), u)); };

%Y Cf. A000010, A000203, A006872, A062401, A064989, A336549, A336550, A353757, A353761, A353763 (denominators), A353764 (positions of 1's).

%K nonn,frac

%O 1,3

%A _Antti Karttunen_, May 10 2022