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4*prime(n)-+3 are both prime.
2

%I #6 Dec 09 2012 13:35:13

%S 1,3,5,8,17,24,29,35,36,67,72,77,79,85,95,98,105,109,145,160,171,175,

%T 189,204,207,215,221,230,263,271,286,321,326,327,335,364,410,444,458,

%U 487,495,501,511,541,551,580,585,633,638,651,654,681,691,708,729,735

%N 4*prime(n)-+3 are both prime.

%H Harvey P. Dale, <a href="/A174011/b174011.txt">Table of n, a(n) for n = 1..3000</a>

%e a(1)=1 because 4*prime(1)-3=5=prime and 4*prime(1)+3=11=prime; a(2)=3 because 4*prime(3)-3=17=prime and 4*prime(3)+3=23=prime.

%t Select[Range[800],And@@PrimeQ[4 Prime[#]+{3,-3}]&] (* _Harvey P. Dale_, Dec 09 2012 *)

%Y Cf. A000040, A002145, A111055.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Mar 05 2010

%E Corrected (24 inserted, 104 replaced by 105, 114 removed etc.) by _R. J. Mathar_, Apr 28 2010