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A179916
Primes with eight embedded primes.
2
12373, 12379, 12713, 13171, 15233, 17333, 17359, 17971, 19373, 19379, 21139, 21319, 22973, 23167, 23197, 23311, 23473, 23537, 23593, 23671, 23677, 23761, 23773, 23977, 24113, 24137, 24179, 24197, 24317, 24337, 24379, 24733, 25237
OFFSET
1,1
COMMENTS
A079066(a(n)) = 8.
MATHEMATICA
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 &]
PROG
(Haskell)
import Data.List (elemIndices)
a179916 n = a179916_list !! (n-1)
a179916_list = map (a000040 . (+ 1)) $ elemIndices 8 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
KEYWORD
base,nonn
AUTHOR
Robert G. Wilson v, Aug 01 2010
STATUS
approved