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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A181559 Numbers with three distinct prime factors (each of which may or may not be repeated) which when concatenated in any order form a prime number.

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%I A181559 #13 Oct 01 2012 16:41:33
%S A181559 3311,23177,27181,32153,36421,41237,53977,86507,110971,125069,142373,
%T A181559 162239,190267,208579,254947,256413,288659,298991,353683,377839,
%U A181559 400631,500981,543337,593747,769239,776797,853811,875483,901949,964481,996611,1053787,1135673
%N A181559 Numbers with three distinct prime factors (each of which may or may not be repeated) which when concatenated in any order form a prime number.
%C A181559 This is a superset of A180679 because in this sequence, unlike in A180679, any of the prime factors may (but need not) be repeated as a factor.
%t A181559 okQ[n_] := Module[{pfs = Transpose[FactorInteger[n]][[1]]}, Length[pfs] == 3 && And @@ PrimeQ[FromDigits /@ (Flatten /@ (IntegerDigits /@ Permutations[pfs]))]]; Select[Range[2100000], okQ]
%Y A181559 Cf. A180679, A217263, A217264, A217265.
%K A181559 nonn,base
%O A181559 1,1
%A A181559 _Harvey P. Dale_, Jan 29 2011