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A039996
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Primes embedded in prime(n).
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18
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1, 1, 1, 1, 1, 2, 2, 1, 3, 2, 2, 3, 1, 2, 2, 3, 2, 1, 2, 2, 3, 2, 2, 1, 2, 1, 2, 2, 1, 4, 3, 4, 5, 3, 1, 2, 3, 2, 3, 5, 4, 1, 2, 3, 4, 2, 3, 4, 3, 3, 4, 4, 3, 3, 4, 3, 2, 4, 3, 2, 4, 4, 3, 4, 4, 5, 3, 4, 4, 2, 4, 4, 4, 5, 5, 3, 3, 4, 1, 1, 3, 2, 4, 3, 3, 3, 1, 3, 2, 2, 3, 4, 2, 1, 1, 3, 2, 3, 5, 3, 4, 3, 3, 2, 4
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,6
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COMMENTS
| a(n) counts substrings of digits of prime(n) which denote primes.
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FORMULA
| a(n) = A039997(prime(n)).
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MATHEMATICA
| f[n_] := Block[{id = IntegerDigits@ Prime@n, len = Floor[ Log[10, Prime@n] + 1]}, Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[id, k, 1], {k, len}], 1]], True]]; Array[f, 105] [From Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 28 2010]
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CROSSREFS
| Different from A039994.
Sequence in context: A094366 A124018 A111709 * A039994 A112200 A112221
Adjacent sequences: A039993 A039994 A039995 * A039997 A039998 A039999
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KEYWORD
| nonn,base
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AUTHOR
| Dave Wilson
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