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A087678
Numbers n such that n + 9 and n - 9 are both prime.
12
14, 20, 22, 28, 32, 38, 50, 52, 62, 70, 80, 88, 92, 98, 118, 122, 140, 148, 158, 172, 182, 188, 190, 202, 220, 232, 242, 248, 260, 272, 302, 322, 340, 358, 388, 392, 410, 430, 440, 448, 452, 458, 470, 500, 512, 532, 578, 608, 610, 622, 650, 652, 668, 682, 692
OFFSET
1,1
LINKS
MATHEMATICA
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 *)
Select[Range[10, 700], AllTrue[#+{9, -9}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Nov 23 2019 *)
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Sep 27 2003
STATUS
approved