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%I #21 Sep 08 2022 08:46:04
%S 43,331,2311,3931,7351,8971,18043,19231,23011,31543,33091,37951,46771,
%T 50551,58543,60631,81043,133711,149731,173671,188143,226843,251791,
%U 296251,310291,319831,364543,385351,395971,412171,417643,439891,474343,540871,625111,631843
%N Primes of the form 2*n^2 + 90*n + 43.
%C Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
%C 2*a(n) + 1939 is a square. - _Vincenzo Librandi_, Apr 09 2015
%H Vincenzo Librandi, <a href="/A217621/b217621.txt">Table of n, a(n) for n = 1..3000</a>
%t Select[Table[2 n^2 + 90 n + 43, {n, 0, 700}], PrimeQ]
%o (Magma) [a: n in [0..700] | IsPrime(a) where a is 2*n^2+90*n+43];
%Y Cf. Primes of the form 2*n^2+2*(2*k+3)*n+(2*k+1): A176549 (k=0), A154577 (k=2), A154592 (k=3), A154601 (k=4), A217494 (k=7), A217495 (k=10), A217496 (k=11), A217497 (k=12), A217498 (k=13), A217499 (k=16), A217500 (k=17), A217501 (k=18), A217620 (k=19), this sequence (k=21).
%Y Subsequence of A002145.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Oct 09 2012
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