cp's OEIS Frontend

A364949 a(n) = gcd(A348717(n), A348717(A163511(n))).

%I A364949 #16 Sep 06 2023 06:58:42
%S A364949 1,2,2,4,2,6,2,8,4,2,2,12,2,2,2,16,2,18,2,4,2,2,2,24,4,2,2,4,2,2,2,32,
%T A364949 2,2,2,36,2,2,2,8,2,6,2,4,2,2,2,48,4,10,2,4,2,2,2,8,2,2,2,4,2,2,2,64,
%U A364949 2,6,2,4,2,10,2,72,2,2,18,4,2,2,2,16,8,2,2,12,2,2,2,8,2,6,10,4,2,2,2,96,2,2,4,20
%N A364949 a(n) = gcd(A348717(n), A348717(A163511(n))).
%H A364949 Antti Karttunen, <a href="/A364949/b364949.txt">Table of n, a(n) for n = 1..16384</a>
%H A364949 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A364949 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F A364949 a(n) = gcd(A348717(n), A364297(n)).
%F A364949 a(2*n) = A364255(2*n) = 2*A364255(n). (Edited Sep 03 2023)
%o A364949 (PARI)
%o A364949 A163511(n) = if(!n,1,my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
%o A364949 A348717(n) = if(1==n, 1, my(f = factor(n), k = primepi(f[1, 1])-1); for (i=1, #f~, f[i, 1] = prime(primepi(f[i, 1])-k)); factorback(f));
%o A364949 A364949(n) = gcd(A348717(n),A348717(A163511(n)));
%Y A364949 Cf. A163511, A348717, A364255, A364297.
%K A364949 nonn
%O A364949 1,2
%A A364949 _Antti Karttunen_, Aug 16 2023