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A118725
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Chen primes for which the reversal is also a Chen prime.
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0
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2, 3, 5, 7, 11, 13, 17, 31, 71, 101, 107, 113, 131, 149, 157, 167, 179, 181, 191, 199, 311, 347, 353, 359, 389, 701, 743, 751, 761, 787, 797, 919, 941, 953, 971, 983, 991, 1009, 1031, 1061, 1091, 1097, 1109, 1151, 1217, 1229, 1259, 1283, 1301, 1409, 1439
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 17 and its reversal 71 are both Chen primes.
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MATHEMATICA
| cpQ[n_]:=Module[{rev=FromDigits[Reverse[IntegerDigits[n]]]}, PrimeOmega[ n+2]<3 && PrimeQ[rev]&&PrimeOmega[rev+2]<3]; Select[Prime[ Range[ 400]], cpQ] (* From Harvey P. Dale, Jul 17 2011 *)
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CROSSREFS
| Cf. A109611.
Sequence in context: A003459 A202264 A186307 * A117835 A120639 A141263
Adjacent sequences: A118722 A118723 A118724 * A118726 A118727 A118728
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KEYWORD
| base,nonn,less
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AUTHOR
| Luc Stevens (lms022(AT)yahoo.com), May 21 2006
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EXTENSIONS
| Corrected by Harvey P. Dale, Jul 17 2011
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