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 A186243 Numbers n such that 6n-5 and 6n-1 are both primes. 8

%I

%S 2,3,4,7,8,12,14,17,18,19,22,28,33,38,39,47,52,53,59,64,67,74,77,78,

%T 82,84,103,108,113,124,127,129,138,143,144,147,148,152,157,162,169,

%U 182,183,203,214,217,218,238,239,242,248,249,259,262,264,267,269

%N Numbers n such that 6n-5 and 6n-1 are both primes.

%C Numbers n such that 6n-5 and 6n-1 are cousin primes. The D = 2 numbers in class II, from page 3 of Weber. - _Jonathan Vos Post_, Feb 14 2011

%H Ivan Neretin, <a href="/A186243/b186243.txt">Table of n, a(n) for n = 1..10000</a>

%H H. J. Weber, <a href="http://arxiv.org/abs/1102.3075">Exceptional Prime Number Twins, Triplets and Multiplets</a>, arXiv:1102.3075 [math.NT], 2011.

%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/CousinPrimes.html">Cousin Primes.</a>

%F {n such that 6*n-5 is in A023200} = {n such that 6*n-1 is in A046132}.

%e a(3) = 4 because 6*4-5 = 19 is prime, and 6*4-1 = 23 is prime.

%t Select[Range[400], PrimeQ[6#-5] && PrimeQ[6#-1] &] (* _Alonso del Arte_, Feb 16 2011 *)

%Y Cf. A023200, A046132, A088765.

%K nonn,easy

%O 1,1

%A _Jonathan Vos Post_, Feb 15 2011

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Last modified June 1 09:49 EDT 2020. Contains 334760 sequences. (Running on oeis4.)