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%I #46 Sep 08 2022 08:44:47
%S 3,5,7,13,17,19,23,29,37,43,59,79,83,89,97,103,127,139,149,163,167,
%T 173,197,199,227,233,239,257,269,293,313,317,337,349,353,367,383,397,
%U 409,419,433,439,457,479,499,503,523,569,577,607,643,659,709,757,769,797,859,863
%N Primes p such that 3*p + 2 is also prime.
%C Also, son primes of order 1. For smallest son primes of order n see A136027 (also definition). For son primes of order 2 see A136082. - _Artur Jasinski_, Dec 12 2007
%H Zak Seidov and Michael De Vlieger, <a href="/A023208/b023208.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from _Zak Seidov_)
%H Rosemary Sullivan and Neil Watling, <a href="http://www.emis.de/journals/INTEGERS/papers/n65/n65.Abstract.html">Independent divisibility pairs on the set of integers from 1 to n</a>, INTEGERS 13 (2013) #A65.
%t n = 1; a = {}; Do[If[PrimeQ[(Prime[k] - 2n)/(2n + 1)], AppendTo[a, (Prime[k] - 2n)/(2n + 1)]], {k, 1, 1000}]; a (* _Artur Jasinski_, Dec 12 2007 *)
%o (PARI) isA023208(n) = isprime(n) && isprime(3*n+2) \\ _Michael B. Porter_, Jan 30 2010
%o (Magma) [n: n in PrimesUpTo(900) | IsPrime(3*n+2)]; // _Vincenzo Librandi_, Nov 20 2010
%o (Haskell)
%o a023208 n = a023208_list !! (n-1)
%o a023208_list = filter ((== 1) . a010051 . (+ 2) . (* 3)) a000040_list
%o -- _Reinhard Zumkeller_, Aug 15 2011
%Y Cf. A023208, A094524, A136019, A136020, A136026, A136027, A136082, A136083, A136084, A136085, A136086, A136087, A136088, A136089, A136090, A136091.
%K nonn,easy
%O 1,1
%A _David W. Wilson_
%E Edited by _N. J. A. Sloane_, May 16 2008 at the suggestion of _R. J. Mathar_
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