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%I #17 Sep 08 2022 08:46:04
%S 23,131,191,911,1223,1451,1571,1823,3323,3671,3851,5651,6323,6791,
%T 7523,8291,9371,10223,12671,15731,16091,16823,25931,28751,29723,39191,
%U 43223,50591,53831,55823,60611,62723,64151,64871,68531,73823,77723,80111,87491,90023
%N Primes of the form 2*n^2 + 50*n + 23.
%C Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
%C 2*a(n)+579 is a square. - _Vincenzo Librandi_, Mar 04 2013
%H Vincenzo Librandi, <a href="/A217496/b217496.txt">Table of n, a(n) for n = 1..3000</a>
%t Select[Table[2 n^2 + 50 n + 23, {n, 0, 500}], PrimeQ]
%o (Magma) [a: n in [0..200] | IsPrime(a) where a is 2*n^2 + 50*n + 23];
%Y Cf. A054723, A176549, A217494.
%Y Subsequence of A002145.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Oct 09 2012