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%I #17 Mar 25 2021 04:56:10
%S 2,3,5,11,131,191,359,953,1229,1583,3851,9221,10061,11579,11939,12119,
%T 12821,13619,14081,14741,14939,15791,15803,16001,16883,18041,19163,
%U 19391,19751,19991,30851,31859,32633,33623,33809,35993,36191,36563
%N Sophie Germain primes for which the reversal is also a Sophie Germain prime.
%C {k such that k is in A005384 and A004086(k) is in A005384}. - _Jonathan Vos Post_, Apr 18 2008
%H Amiram Eldar, <a href="/A118573/b118573.txt">Table of n, a(n) for n = 1..10000</a>
%e 359 is in the sequence because it is a Sophie Germain prime and its reversal 953 is also a Sophie Germain prime.
%t Select[Prime[Range[10000]], PrimeQ[2*# + 1] && PrimeQ[FromDigits[Reverse[ IntegerDigits[ # ]]]] && PrimeQ[2*FromDigits[Reverse[IntegerDigits[ # ]]] + 1] &] (* _Stefan Steinerberger_, May 18 2008 *)
%t fQ[n_] := (rp = FromDigits@ Reverse@ IntegerDigits@n; PrimeQ[2n + 1] && PrimeQ[rp] && PrimeQ[2rp + 1]); Select[Prime@ Range@4093, fQ@# &] (* _Robert G. Wilson v_, May 09 2006 *)
%Y Cf. A004086, A005384.
%Y A051835 is a subsequence.
%K base,nonn
%O 1,1
%A Luc Stevens (lms022(AT)yahoo.com), May 07 2006
%E More terms from _Robert G. Wilson v_ and Adam Panagos (adam.panagos(AT)gmail.com), May 09 2006
%E Edited by _N. J. A. Sloane_, Mar 02 2009 at the suggestion of _R. J. Mathar_
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