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A087681 Numbers n such that n + 6 and n - 6 are both prime. 8
11, 13, 17, 23, 25, 35, 37, 47, 53, 65, 67, 73, 77, 95, 103, 107, 133, 143, 145, 157, 173, 185, 187, 205, 217, 233, 235, 245, 257, 263, 275, 277, 287, 343, 353, 373, 395, 403, 415, 425, 427, 437, 455, 473, 485, 493, 497, 515, 563, 593, 607, 613, 625, 637, 647 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Many terms are of the form 5 + n + n^2 or 5 + 2*n^2: A054794.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

f[n_]:=PrimeQ[n-6]&&PrimeQ[n+6]; lst={}; Do[If[f[n], AppendTo[lst, n]], {n, 2, 7!, 1}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 12 2009 *)

Select[Range[2, 700], AllTrue[#+{6, -6}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 26 2019 *)

CROSSREFS

Cf. A054794.

Cf. A014574, A087678-A087683, A087695-A087697, A088766.

Sequence in context: A036977 A120168 A260715 * A137669 A152470 A191023

Adjacent sequences:  A087678 A087679 A087680 * A087682 A087683 A087684

KEYWORD

easy,nonn

AUTHOR

Zak Seidov, Sep 27 2003

STATUS

approved

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Last modified September 26 01:25 EDT 2020. Contains 337346 sequences. (Running on oeis4.)