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%I #36 Sep 08 2022 08:44:47
%S 3,7,13,19,31,37,61,67,73,79,97,103,109,139,151,163,181,229,241,271,
%T 283,307,313,367,373,409,439,457,523,541,613,643,661,709,727,733,739,
%U 769,787,811,829,859,877,937,991,997,1039,1063,1069,1087,1117,1123,1153,1171
%N Numbers m such that m and 2*m + 5 are both prime.
%H John Cerkan, <a href="/A023205/b023205.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) == 1 (mod 6) for n>=2. - _John Cerkan_, Sep 07 2016
%p A023205:=n->`if`(isprime(n) and isprime(2*n+5), n, NULL): seq(A023205(n), n=1..3*10^3); # _Wesley Ivan Hurt_, Sep 08 2016
%t Select[Prime@Range@250, PrimeQ[2#+5]&] (* _Vladimir Joseph Stephan Orlovsky_, Apr 25 2011 *)
%o (Magma) [n: n in [0..100000] | IsPrime(n) and IsPrime(2*n+5)] // _Vincenzo Librandi_, Aug 04 2010
%Y Subsequence of primes of A089038.
%Y Cf. A005384, A023204.
%K nonn
%O 1,1
%A _David W. Wilson_, Jun 14 1998
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