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%I #41 Sep 08 2022 08:46:11
%S 2,3,13,29,89,113,199,229,263,281,317,337,349,541,593,673,683,827,857,
%T 911,929,971,997,1069,1109,1291,1399,1481,1657,1693,1733,1759,1783,
%U 1877,1907,1931,2003,2053,2089,2377,2543,2551,2777,2903,3011,3023,3041,3089,3181,3251,3361,3617,3671
%N Primes prime(n) such that prime(2*n) - n is prime.
%C Primes prime(n) such that A031215(n) - n is prime.
%e 3 is in this sequence because 3 is prime(2) and prime(2*2) - 2 = prime(4)- 2 = 7 - 2 = 5 is prime.
%p seq(`if`(isprime(ithprime(2*n)-n),ithprime(n),NULL),n=1..1000); # _Robert Israel_, Apr 13 2015
%t Prime[Select[Range[555],PrimeQ[Prime[2*#]-#]&]] (* _Ivan N. Ianakiev_, Apr 14 2015 *)
%o (Magma) [NthPrime(n): n in [1..550] | IsPrime(NthPrime(2*n)-n)];
%o (PARI) for(n=1,10^3,if(isprime(prime(2*n)-n),print1(prime(n),", "))) \\ _Derek Orr_, Apr 14 2015
%Y Cf. A031215.
%K nonn,easy
%O 1,1
%A _Juri-Stepan Gerasimov_, Apr 13 2015
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