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Primes of the form 5n^2 - 7.
1

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

%S 13,73,173,313,1613,1993,3373,4493,5113,6473,7213,7993,13513,19213,

%T 21773,25913,33613,36973,38713,40493,46073,49993,58313,60493,67273,

%U 71993,74413,76873,95213,115513,131213,154873,172973,176713,204013

%N Primes of the form 5n^2 - 7.

%H Vincenzo Librandi, <a href="/A201788/b201788.txt">Table of n, a(n) for n = 1..5000</a>

%t Select[Table[5n^2-7,{n,2,1000}],PrimeQ]

%o (Magma) [a: n in [2..400] | IsPrime(a) where a is 5*n^2-7];

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Dec 05 2011