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%I #59 Sep 08 2022 08:45:06
%S 3,13,31,241,307,463,757,1123,1723,3307,3541,4831,5113,5701,6007,8011,
%T 9901,10303,11131,12433,13807,14281,17293,20023,20593,21757,23563,
%U 24181,26083,28057,30103,35911,41413,43891,46441,53593,60271,78121,82657,86143,95791,108571,123553,127807,136531,145543,147073,156421
%N Primes of the form 4*k^2 - 10*k + 7 with k positive.
%C Primes of the form k^2 + k + 1 with k odd and positive. - _Peter Munn_, Jan 27 2018
%C Primes of the form A000217(2*k) + A000217(2*k+2). - _J. M. Bergot_, May 09 2018
%H Muniru A Asiru, <a href="/A073337/b073337.txt">Table of n, a(n) for n = 1..5000</a>
%e 3 is a term because for k=2, 4*k^2 - 10*k + 7 = 3 a prime.
%e 7 is not a term because 7 can only be obtained with k=0 or k=5/2.
%p select(isprime, [seq(4*n^2-10*n+7 ,n=2..300)]); # _Muniru A Asiru_, Apr 15 2018
%t Select[Table[4 n^2 - 10 n + 7, {n, 1, 200}], PrimeQ] (* _Vincenzo Librandi_, Dec 23 2019 *)
%o (PARI) select(isprime,vector(300,k,4*k^2 - 10*k + 7)) \\ _Joerg Arndt_, Feb 28 2018
%o (GAP) Filtered(List([2..300],n->4*n^2-10*n+7),IsPrime); # _Muniru A Asiru_, Apr 15 2018
%o (Magma) [a: n in [1..400] | IsPrime(a) where a is 4*n^2 - 10*n + 7]; // _Vincenzo Librandi_, Dec 23 2019
%Y Cf. A054554, A073338, A168026.
%Y Subset of A002383.
%K easy,nonn
%O 1,1
%A _Zak Seidov_, Aug 25 2002
%E Edited by _Dean Hickerson_, Aug 28 2002
%E a(1)=7 inserted and typo in Mathematica code corrected by _Vincenzo Librandi_, Dec 09 2011
%E Incorrect term 7 removed by _Joerg Arndt_, Feb 28 2018
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