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%I #45 Jan 06 2024 10:28:30
%S 3,3,5,3,7,3,5,11,5,3,5,13,3,7,3,7,17,3,5,19,5,3,11,3,23,3,7,11,5,13,
%T 3,7,29,13,3,31,3,3,5,17,5,3,7,37,3,19,17,3,5,3,41,3,19,43,7,11,3,23,
%U 47,7,3,7,3,5,3,23,13,53,3,5,7,5,3,29,3,59,3,11
%N a(n) = second smallest distinct prime factor of A126706(n).
%C Since omega(A126706(n)) = A001221(A126706(n)) > 1, and since A126706 is infinite, a(n) exists for all n.
%F a(n) = A119288(A126706(n)) > 2.
%e Let b(n) = A126706(n).
%e a(1) = 3 since b(1) = 12 = 2^2 * 3.
%e a(2) = 3 since b(2) = 18 = 2 * 3^2.
%e a(3) = 5 since b(3) = 20 = 2^2 * 5, etc.
%t FactorInteger[#][[2, 1]] & /@ Select[Range[250], PrimeOmega[#] > PrimeNu[#] > 1 &]
%Y Cf. A119288, A126706.
%K nonn,easy
%O 1,1
%A _Michael De Vlieger_, Jan 05 2024