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A028873 Numbers n such that n^2 - 3 is prime. 12
4, 8, 10, 14, 20, 26, 32, 34, 40, 44, 46, 58, 64, 68, 80, 86, 88, 92, 98, 110, 112, 118, 124, 128, 136, 140, 142, 146, 164, 172, 190, 194, 202, 206, 208, 218, 220, 250, 254, 266, 268, 296, 298, 304, 310, 320, 322, 326, 328, 332, 340, 350, 356, 362, 370, 416, 418 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

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

Eric Weisstein's World of Mathematics, Near-Square Prime

EXAMPLE

8^2 - 3 = 61 is prime, so 8 is in the sequence.

MATHEMATICA

a[n_]:=n^x-y; lst={}; x=2; y=3; Do[If[PrimeQ[a[n]], AppendTo[lst, n]], {n, 0, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 03 2009 *)

PROG

(MAGMA) [n: n in [2..10000] |IsPrime(n^2-3)] // Vincenzo Librandi, Aug 05 2010

(PARI) is(n)=isprime(n^2-3) \\ Charles R Greathouse IV, Jul 02 2013

CROSSREFS

Sequence in context: A063087 A120064 A191330 * A252662 A153975 A020169

Adjacent sequences:  A028870 A028871 A028872 * A028874 A028875 A028876

KEYWORD

nonn,easy

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified January 22 22:38 EST 2018. Contains 298093 sequences.