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%I #9 Dec 10 2023 17:53:25
%S 1,2,2,2,2,6,2,2,2,6,2,6,2,6,10,2,2,6,2,14,10,6,2,6,2,6,2,14,2,18,2,2,
%T 10,6,55,6,2,6,10,14,2,78,2,14,4,6,2,6,2,6,10,14,2,6,55,6,10,6,2,42,2,
%U 6,10,2,22,78,2,14,10,42,2,6,2,6,10,14,187,78,2,14,2,6,2,78,22,6,10,38,2,18,34,14,10,6,55,6,2,6,46,14,2,78,2,38,20
%N Product prime(1+((n-1) mod (p-1))), where p ranges over distinct prime divisors of n.
%C a(n) is a power of 2 if and only if n is a term of A087441.
%H Antti Karttunen, <a href="/A324291/b324291.txt">Table of n, a(n) for n = 1..16384</a>
%F a(n) = Product_{p|n, p prime} A000040(1+((n-1) mod (p-1))).
%F A001222(a(n)) = A001221(n).
%o (PARI) A324291(n) = if(1==n, 1, my(f=factor(n), m=1); for(i=1, #f[, 1], m *= prime(1+((n-1)%(f[i, 1]-1)))); (m));
%Y Cf. A000040, A087441, A324290, A324292 (rgs-transform).
%K nonn
%O 1,2
%A _Antti Karttunen_, Feb 23 2019