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%I #10 Oct 10 2019 01:08:10
%S 6,143,10403,1022117,100160063,10002200057,1000036000099,
%T 100000980001501,10000004400000259,1000000016000000063,
%U 100000000520000000627,10000000002200000000057,1000000000100000000002379,100000000000880000000001887,10000000000009800000000002077
%N Smallest number with two distinct prime factors both of length n.
%e a(3)=10403 -> equals 101 * 103.
%t tdpf[n_]:=Module[{f1=NextPrime[Floor[Sqrt[10^n]]]},{IntegerLength[f1], f1* NextPrime[f1]}];Join[{6},Table[SelectFirst[Array[tdpf,50],#[[1]]==n&],{n,2,20}][[All,2]]] (* _Harvey P. Dale_, Apr 06 2018 *)
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Jan 04 1999
%E Corrected and extended by _Harvey P. Dale_, Apr 06 2018