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%I #10 Mar 05 2019 18:19:28
%S 1,1,1,1,1,6,1,1,1,2,3,4,1,3,1,1,1,2,1,2,1,6,3,12,1,1,1,1,1,6,1,1,1,2,
%T 3,28,1,6,1,10,1,2,3,12,1,18,15,4,1,1,3,1,1,6,1,3,1,2,3,4,1,3,1,1,1,2,
%U 1,4,1,6,3,8,7,2,3,28,1,6,1,2,1,2,3,28,1,6,3,120,1,2,1,6,1,90,3,12,1,1,1,7,1,6,3,5,7,2
%N a(n) = A009194(A005940(1+n)), where A005940 is the Doudna sequence and A009194(n) = gcd(n,sigma(n)).
%H Antti Karttunen, <a href="/A324394/b324394.txt">Table of n, a(n) for n = 0..16384</a>
%H Antti Karttunen, <a href="/A324394/a324394.txt">Data supplement: n, a(n) computed for n = 0..65537</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = A009194(A005940(1+n)) = gcd(A005940(1+n), A324054(n)).
%o (PARI) A324394(n) = { my(m1=1,m2=1,p=2,mp=p*p); while(n, if(!(n%2), p=nextprime(1+p); mp = p*p, m1 *= p; if(3==(n%4),mp *= p,m2 *= (mp-1)/(p-1))); n>>=1); gcd(m1,m2); };
%o (PARI)
%o A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
%o A009194(n) = gcd(n, sigma(n));
%o A324394(n) = A009194(A005940(1+n));
%Y Cf. A009194, A324054, A324055, A324058, A324349, A324395.
%K nonn
%O 0,6
%A _Antti Karttunen_, Mar 05 2019
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