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%I #8 Dec 30 2020 19:59:21
%S 1,1,1,1,3,1,5,1,1,1,3,1,1,1,1,1,9,1,11,1,1,1,7,1,3,1,1,1,15,1,9,1,1,
%T 1,1,1,5,1,1,1,21,1,23,1,3,1,13,1,5,1,1,1,29,1,9,1,1,1,15,1,33,1,1,1,
%U 1,1,35,1,1,5,9,1,39,1,1,1,1,1,41,1,1,1,11,1,3,1,1,1,3,1,1,1,1,1,1,1,25,1,3,1,51,1,53,1,3
%N a(n) = gcd(A003961(n)-1, A339904(n)).
%C Odd part of A340071(n).
%H Antti Karttunen, <a href="/A340074/b340074.txt">Table of n, a(n) for n = 1..8191</a>
%H Antti Karttunen, <a href="/A340074/a340074.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>
%F a(n) = gcd(A003961(n)-1, A339904(n)).
%F a(n) = A000265(A340071(n)).
%F a(n) = A339904(n) / A340075(n).
%o (PARI)
%o A000265(n) = (n>>valuation(n,2));
%o A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
%o A339904(n) = A000265(eulerphi(A003961(n)));
%o A340074(n) = gcd(A003961(n)-1, A339904(n));
%Y Cf. A000265, A003961, A339904, A340071, A340075.
%K nonn
%O 1,5
%A _Antti Karttunen_, Dec 29 2020
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