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A153118 Primes p such that p^2 +- 18 are also primes. 1
5, 7, 11, 17, 29, 41, 43, 59, 71, 83, 223, 283, 311, 347, 389, 433, 479, 601, 619, 881, 907, 967, 983, 991, 1039, 1093, 1151, 1471, 1567, 1723, 1873, 1877, 1907, 1931, 1933, 1987, 2309, 2531, 2953, 3037, 3461, 3539, 3853, 4001, 4003, 4007, 4073, 4091, 4253 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

fQ[n_]:=PrimeQ[n^2-18]&&PrimeQ[n^2+18]; lst={}; Do[If[fQ@Prime[n], AppendTo[lst, Prime[n]]], {n, 7!}]; lst

Select[Prime[Range[700]], And@@PrimeQ/@{#^2+18, #^2-18}&]  (* Harvey P. Dale, Mar 12 2011 *)

PROG

(MAGMA) [p: p in PrimesUpTo(4500) | IsPrime(p^2-18) and IsPrime(p^2+18)]; // Vincenzo Librandi, Apr 09 2013

CROSSREFS

Cf. A153116.

Sequence in context: A106862 A027690 A087200 * A145987 A060449 A046140

Adjacent sequences:  A153115 A153116 A153117 * A153119 A153120 A153121

KEYWORD

nonn,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, Dec 18 2008, Dec 20 2008

STATUS

approved

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Last modified February 26 17:19 EST 2020. Contains 332293 sequences. (Running on oeis4.)