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A028883 Primes of form n^2 - 7. 4
2, 29, 137, 317, 569, 1289, 2297, 2909, 3593, 4349, 8093, 9209, 11657, 17417, 19037, 24329, 26237, 30269, 34589, 36857, 41609, 46649, 49277, 51977, 57593, 60509, 72893, 93629, 101117, 108893, 129593, 133949, 147449, 152093, 166457, 191837, 202493, 219017, 224669 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of primes of A028881. - Michel Marcus, Apr 11 2015

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..3000

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

MAPLE

A028883:=n->`if`(isprime(n^2-7), n^2-7, NULL): seq(A028883(n), n=1..500); # Wesley Ivan Hurt, Apr 11 2015

MATHEMATICA

lst={}; Do[s=n^2; If[PrimeQ[p=s-7], AppendTo[lst, p]], {n, 7!}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 26 2008 *)

Select[Range[3, 410]^2-7, PrimeQ] (* Harvey P. Dale, Sep 20 2011 *)

PROG

(MAGMA) [a: n in [3..500] | IsPrime(a) where a is n^2-7]; // Vincenzo Librandi, Dec 01 2011

(PARI) lista(nn) = forprime (n=1, nn, if (issquare(n+7), print1(n, ", "))) \\ Michel Marcus, Apr 11 2015

CROSSREFS

Sequence in context: A123004 A062618 A128842 * A024200 A132412 A009772

Adjacent sequences:  A028880 A028881 A028882 * A028884 A028885 A028886

KEYWORD

nonn,easy

AUTHOR

Patrick De Geest

EXTENSIONS

More terms from Michel Marcus, Apr 11 2015

STATUS

approved

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