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%I #12 Sep 08 2022 08:45:39
%S 2,5,11,17,41,47,59,89,107,131,137,149,167,191,251,269,311,317,389,
%T 401,419,431,461,467,479,521,587,599,641,677,797,809,839,857,929,941,
%U 947,977,1031,1061,1097,1109,1181,1187,1229,1301,1307,1319,1361,1367,1409
%N Primes p such that 2*p + 19 is also prime.
%H Vincenzo Librandi, <a href="/A153145/b153145.txt">Table of n, a(n) for n = 1..1000</a>
%e For n=2, 2*n+19 = 23 is prime, so 2 is in the sequence.
%t Select[Prime[Range[2000]],PrimeQ[2 # + 19] &] (* _Vincenzo Librandi_, Oct 20 2012 *)
%o (Magma) [p: p in PrimesUpTo(1500) | IsPrime(2*p+19)];
%Y Cf. A153143 (m and 2*m+19 are both prime), A005384 (Sophie Germain primes, m and 2*m+1 are both prime), A023204 (m and 2*m+3 are both prime), A023205 (m and 2*m+5 are both prime), A023206 (m and 2*m+7 are both prime), A023207 (m and 2*m+9 are both prime).
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 19 2008
%E Edited, corrected and extended by _Klaus Brockhaus_, Dec 22 2008