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%I #13 Oct 01 2012 16:41:33
%S 3311,23177,27181,32153,36421,41237,53977,86507,110971,125069,142373,
%T 162239,190267,208579,254947,256413,288659,298991,353683,377839,
%U 400631,500981,543337,593747,769239,776797,853811,875483,901949,964481,996611,1053787,1135673
%N 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 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 okQ[n_] := Module[{pfs = Transpose[FactorInteger[n]][[1]]}, Length[pfs] == 3 && And @@ PrimeQ[FromDigits /@ (Flatten /@ (IntegerDigits /@ Permutations[pfs]))]]; Select[Range[2100000], okQ]
%Y Cf. A180679, A217263, A217264, A217265.
%K nonn,base
%O 1,1
%A _Harvey P. Dale_, Jan 29 2011