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Primes of the form 7n^2 + 3.
1

%I #6 Sep 08 2022 08:46:01

%S 3,31,2803,3391,10111,32371,34303,67231,70003,87811,114691,161731,

%T 179203,231871,285631,302851,338803,409951,473203,502771,588703,

%U 596851,621631,638431,672703,753091,809203,1075651,1246591,1294303,1367551

%N Primes of the form 7n^2 + 3.

%H Vincenzo Librandi, <a href="/A201604/b201604.txt">Table of n, a(n) for n = 1..5000</a>

%t Select[Table[7n^2+3,{n,0,3000}],PrimeQ]

%o (Magma) [a: n in [0..700] | IsPrime(a) where a is 7*n^2+3];

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Dec 03 2011