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%I #25 Sep 08 2022 08:46:04
%S 769,1381,1741,2137,3037,3541,4657,7321,9697,22441,26437,30757,35401,
%T 37021,38677,47497,49369,55201,61357,72337,79357,81769,96997,99661,
%U 105097,134437,188869,207769,211657,227569,256801,306301,330241,469237,480937,492781,510817
%N Primes of the form 2*n^2 + 46*n + 21.
%C Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
%C 2*a(n)+487 is a square. - _Vincenzo Librandi_, Mar 04 2013
%H Vincenzo Librandi, <a href="/A217495/b217495.txt">Table of n, a(n) for n = 1..3000</a>
%t Select[Table[2 n^2 + 46 n + 21, {n, 500}], PrimeQ]
%o (Magma) [a: n in [1..500] | IsPrime(a) where a is 2*n^2+46*n+21];
%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), this sequence (k=10), A217496 (k=11), A217497 (k=12), A217498 (k=13), A217499 (k=16), A217500 (k=17), A217501 (k=18), A217620 (k=19), A217621 (k=21).
%Y Cf. A054723.
%Y Subsequence of A002144.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Oct 09 2012
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