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%I #7 Apr 19 2016 01:16:08
%S 2,5,11,37,13,23,19,23,37,127,47,61,61,47,67,61,277,83,79,97,127,83,
%T 101,131,269,109,131,109,113,157,137,181,157,181,151,173,173,179,173,
%U 211,223,251,193,197,223,233,223,251,271,241,239,269,293,281,313,347,293
%N Smallest prime factor of A111392(n).
%C For all i, if i<n+2 then GCD(p_i,A111392(n))=1, where p_i is i-th prime.
%C A111392: a(n) = Product_{i=1..n-1} (Product_{k=1..i} p_k + Product_{k=i+1..n} p_k). - _Robert G. Wilson v_, Dec 22 2005
%t f[n_] := Product[(Product[Prime[k], {k, i}] + Product[Prime[k], {k, i + 1, n}]), {i, n - 1}]; f[1] = 2; g[n_] := Block[{k = 1}, While[Mod[f[n], Prime[k]] != 0, k++ ]; Prime@k]; Array[g, 20] (* _Robert G. Wilson v_ *)
%Y Cf. A111392.
%K nonn
%O 1,1
%A _Yasutoshi Kohmoto_, Dec 15 2005
%E More terms from _Robert G. Wilson v_, Dec 22 2005