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%I #23 Sep 08 2022 08:45:12
%S 0,7,10,12,15,16,22,25,27,31,36,37,40,46,51,52,55,57,60,61,67,75,85,
%T 87,90,97,102,106,111,120,136,151,156,157,162,171,172,177,180,186,192,
%U 202,205,211,220,222,225,237,240,241,250,255,261,267,271,277,282,286,291,292
%N Numbers k such that k^2 - 7*k + 7 is prime.
%D M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna, 1988.
%D Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta, UTET, CittaStudiEdizioni, Milano, 1997.
%H Vincenzo Librandi, <a href="/A089373/b089373.txt">Table of n, a(n) for n = 1..10000</a>
%t Column[(0),Select[Range[6,200],PrimeQ[ #^2-7#+7]&]] (* _Vincenzo Librandi_, Dec 12 2011 *)
%o (Magma) [0],[n: n in [6..300] | IsPrime(n^2 - 7*n + 7)]; // _Vincenzo Librandi_, Dec 12 2011
%o (PARI) is(n)=isprime(n^2-7*n+7) \\ _Charles R Greathouse IV_, May 22 2017
%o (GAP) Concatenation([0],Filtered([7..300],k->IsPrime(k^2-7*k+7))); # _Muniru A Asiru_, Nov 24 2018
%Y Cf. A089376 (primes of the form k^2 - 7*k + 7).
%K easy,nonn
%O 1,2
%A _Giovanni Teofilatto_, Dec 27 2003
%E More terms from _David Wasserman_, Sep 15 2005
%E a(1)=0 inserted by _Vincenzo Librandi_, Dec 12 2011
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