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A118725 Chen primes for which the reversal is also a Chen prime. 0
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; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

17 and its reversal 71 are both Chen primes.

MATHEMATICA

cpQ[n_]:=Module[{rev=FromDigits[Reverse[IntegerDigits[n]]]}, PrimeOmega[ n+2]<3 && PrimeQ[rev]&&PrimeOmega[rev+2]<3]; Select[Prime[ Range[ 400]], cpQ] (* Harvey P. Dale, Jul 17 2011 *)

CROSSREFS

Cf. A109611.

Sequence in context: A202264 A253717 A186307 * A117835 A120639 A141263

Adjacent sequences:  A118722 A118723 A118724 * A118726 A118727 A118728

KEYWORD

base,nonn,less

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), May 21 2006

EXTENSIONS

Corrected by Harvey P. Dale, Jul 17 2011

STATUS

approved

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Last modified January 22 08:47 EST 2018. Contains 298042 sequences.