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A087678 Numbers n such that n + 9 and n - 9 are both prime. 12

%I #21 Nov 23 2019 20:51:35

%S 14,20,22,28,32,38,50,52,62,70,80,88,92,98,118,122,140,148,158,172,

%T 182,188,190,202,220,232,242,248,260,272,302,322,340,358,388,392,410,

%U 430,440,448,452,458,470,500,512,532,578,608,610,622,650,652,668,682,692

%N Numbers n such that n + 9 and n - 9 are both prime.

%H Daniel Starodubtsev, <a href="/A087678/b087678.txt">Table of n, a(n) for n = 1..10000</a>

%t f[n_]:=PrimeQ[n-9]&&PrimeQ[n+9]; lst={};Do[If[f[n],AppendTo[lst,n]],{n,6,8!,2}];lst (* _Vladimir Joseph Stephan Orlovsky_, Oct 09 2009 *)

%t Select[Range[10,700],AllTrue[#+{9,-9},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Nov 23 2019 *)

%Y Cf. A014574, A087679-A087683, A087695-A087697, A088769.

%K easy,nonn

%O 1,1

%A _Zak Seidov_, Sep 27 2003

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Last modified April 19 15:34 EDT 2024. Contains 371794 sequences. (Running on oeis4.)