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A179909
Primes with only one embedded prime.
15
13, 17, 29, 31, 43, 47, 59, 67, 71, 79, 83, 97, 103, 107, 151, 163, 191, 199, 269, 281, 349, 421, 461, 463, 487, 509, 569, 607, 641, 661, 701, 709, 769, 787, 811, 821, 863, 877, 887, 907, 911, 919, 941, 1021, 1051, 1061, 1063, 1087, 1091, 1201, 1249, 1409
OFFSET
1,1
COMMENTS
A079066(a(n)) = 1.
LINKS
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@ 230, f@# == 2 &]
PROG
(Haskell)
import Data.List (elemIndices)
a179909 n = a179909_list !! (n-1)
a179909_list = map (a000040 . (+ 1)) $ elemIndices 1 a079066_list
-- Reinhard Zumkeller, Jul 19 2011
KEYWORD
base,nonn
AUTHOR
Robert G. Wilson v, Aug 01 2010
STATUS
approved