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Search: id:A114019
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| A114019 |
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Largest n-digit prime whose digit reversal is also prime. |
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+0
4
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| 7, 97, 991, 9967, 99989, 999983, 9999971, 99999827, 999999893, 9999999967, 99999999977, 999999999959, 9999999999799, 99999999999959, 999999999999877, 9999999999999571, 99999999999997997, 999999999999999737
(list; graph; listen)
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OFFSET
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1,1
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MATHEMATICA
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f[n_] := Block[{k = 10^n}, While[ !PrimeQ[k] || !PrimeQ[FromDigits@Reverse@IntegerDigits@k], k-- ]; k]; Array[f, 19] (* Robert G. Wilson v *)
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CROSSREFS
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Cf. A113018.
Sequence in context: A030540 A071361 A007810 this_sequence A127892 A125590 A068694
Adjacent sequences: A114016 A114017 A114018 this_sequence A114020 A114021 A114022
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 12 2005
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EXTENSIONS
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More terms from Robert G. Wilson v (rgwv(at)rgwv.com), Nov 19 2005
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