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A028882 Numbers n such that n^2 - 7 is prime. 6
3, 6, 12, 18, 24, 36, 48, 54, 60, 66, 90, 96, 108, 132, 138, 156, 162, 174, 186, 192, 204, 216, 222, 228, 240, 246, 270, 306, 318, 330, 360, 366, 384, 390, 408, 438, 450, 468, 474, 480, 492, 498, 522, 570, 576, 582, 606, 612, 618, 624, 636, 642, 660, 678, 708 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Edward Jiang, Table of n, a(n) for n = 1..1000

P. De Geest, Palindromic Quasipronics of the form n(n+x)

MATHEMATICA

f[n_]:=PrimeQ[n^2-7]; lst={}; Do[If[f[n], AppendTo[lst, n]], {n, 3, 7!, 1}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 12 2009 *)

Select[Range[3, 800], PrimeQ[#^2-7]&] (* Harvey P. Dale, Jul 21 2013 *)

PROG

(MAGMA) [n: n in [3..1000] |IsPrime(n^2-7)] // Vincenzo Librandi, Nov 18 2010

(PARI) for(n=3, 1000, if(isprime(n^2-7), print1(n, ", "))) \\ Edward Jiang, Aug 06 2014

CROSSREFS

Sequence in context: A079830 A160744 A160738 * A154907 A273015 A242297

Adjacent sequences:  A028879 A028880 A028881 * A028883 A028884 A028885

KEYWORD

nonn

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified February 19 19:30 EST 2020. Contains 332047 sequences. (Running on oeis4.)