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A089373 Numbers k such that k^2 - 7*k + 7 is prime. 2
0, 7, 10, 12, 15, 16, 22, 25, 27, 31, 36, 37, 40, 46, 51, 52, 55, 57, 60, 61, 67, 75, 85, 87, 90, 97, 102, 106, 111, 120, 136, 151, 156, 157, 162, 171, 172, 177, 180, 186, 192, 202, 205, 211, 220, 222, 225, 237, 240, 241, 250, 255, 261, 267, 271, 277, 282, 286, 291, 292 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
REFERENCES
M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna, 1988.
Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta, UTET, CittaStudiEdizioni, Milano, 1997.
LINKS
MATHEMATICA
Column[(0), Select[Range[6, 200], PrimeQ[ #^2-7#+7]&]] (* Vincenzo Librandi, Dec 12 2011 *)
PROG
(Magma) [0], [n: n in [6..300] | IsPrime(n^2 - 7*n + 7)]; // Vincenzo Librandi, Dec 12 2011
(PARI) is(n)=isprime(n^2-7*n+7) \\ Charles R Greathouse IV, May 22 2017
(GAP) Concatenation([0], Filtered([7..300], k->IsPrime(k^2-7*k+7))); # Muniru A Asiru, Nov 24 2018
CROSSREFS
Cf. A089376 (primes of the form k^2 - 7*k + 7).
Sequence in context: A128783 A024586 A050419 * A184114 A345478 A295797
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, Dec 27 2003
EXTENSIONS
More terms from David Wasserman, Sep 15 2005
a(1)=0 inserted by Vincenzo Librandi, Dec 12 2011
STATUS
approved

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Last modified June 12 14:48 EDT 2024. Contains 373331 sequences. (Running on oeis4.)