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%I #19 Apr 23 2014 01:32:07
%S 23,37,53,73,127,139,157,167,193,211,227,229,241,251,263,277,307,331,
%T 383,389,419,433,439,443,457,467,503,521,541,557,563,577,587,599,619,
%U 631,643,647,659,677,683,727,751,757,761,827,829,839,857,859,883,929
%N Primes with two embedded primes.
%C It appears that p having n embedded primes means that the set of prime integers generated by contiguous proper substrings of p has size n.
%C A079066(a(n)) = 2.
%H Reinhard Zumkeller, <a href="/A179910/b179910.txt">Table of n, a(n) for n = 1..1000</a>
%t f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 160, f@# == 3 &]
%t Select[ Prime@ Range@ 160, Function[ n, Length@ Select[ Union[ FromDigits /@ (Flatten[ Table[ Partition[#, k, 1], {k, Length@ # - 1}], 1] &)@ IntegerDigits@ n], PrimeQ]]@ # == 2 &] (* _Michael Somos_, Jan 13 2011 *)
%o (Haskell)
%o import Data.List (elemIndices)
%o a179910 n = a179910_list !! (n-1)
%o a179910_list = map (a000040 . (+ 1)) $ elemIndices 2 a079066_list
%o -- _Reinhard Zumkeller_, Jul 19 2011
%Y Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.
%K base,nonn
%O 1,1
%A _Robert G. Wilson v_, Aug 01 2010
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