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Primes with eight embedded primes.
2

%I #6 Feb 22 2013 21:38:32

%S 12373,12379,12713,13171,15233,17333,17359,17971,19373,19379,21139,

%T 21319,22973,23167,23197,23311,23473,23537,23593,23671,23677,23761,

%U 23773,23977,24113,24137,24179,24197,24317,24337,24379,24733,25237

%N Primes with eight embedded primes.

%C A079066(a(n)) = 8.

%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@ 2790, f@# == 9 &]

%o (Haskell)

%o import Data.List (elemIndices)

%o a179916 n = a179916_list !! (n-1)

%o a179916_list = map (a000040 . (+ 1)) $ elemIndices 8 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