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A118573 Sophie Germain primes for which the reversal is also a Sophie Germain prime. +0
1
2, 3, 5, 11, 131, 191, 359, 953, 1229, 1583, 3851, 9221, 10061, 11579, 11939, 12119, 12821, 13619, 14081, 14741, 14939, 15791, 15803, 16001, 16883, 18041, 19163, 19391, 19751, 19991, 30851, 31859, 32633, 33623, 33809, 35993, 36191, 36563 (list; graph; listen)
OFFSET

1,1

EXAMPLE

359 is in the sequence because (1) it is a Sophie Germain prime, and (2) the reversal 953 is also a Sophie Germain prime.

MATHEMATICA

fQ[n_] := (rp = FromDigits@ Reverse@ IntegerDigits@n; PrimeQ[2n + 1] && PrimeQ[rp] && PrimeQ[2rp + 1]); Select[Prime@ Range@4093, fQ@# &] - Robert G. Wilson v (rgwv(at)rgwv.com), May 09 2006

CROSSREFS

Cf. A005384.

Sequence in context: A050444 A117701 A056163 this_sequence A137453 A051835 A075883

Adjacent sequences: A118570 A118571 A118572 this_sequence A118574 A118575 A118576

KEYWORD

base,nonn

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), May 07 2006

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(at)rgwv.com) and Adam Panagos (adam.panagos(AT)gmail.com), May 09 2006

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Last modified August 29 17:54 EDT 2008. Contains 143238 sequences.


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