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%I #11 Sep 08 2022 08:46:08
%S 661,1201,2281,2713,3181,4801,5413,8221,9013,12541,13513,17761,18913,
%T 20101,32413,33961,38821,51421,72481,91921,94513,108013,110821,134581,
%U 137713,153913,167521,211801,223681,265621,274441,335281,345181,365413,370561,440761,560641
%N Primes of the form 2*n^2+30*n+13.
%C Subsequence of A142104.
%C Conjecture: except 2281, 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
%C 2*a(n) + 199 is a square. - _Vincenzo Librandi_, Apr 10 2015
%H Vincenzo Librandi, <a href="/A243889/b243889.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Table[2 n^2 + 30 n + 13, {n, 1000}], PrimeQ]
%o (Magma) [a: n in [1..800] | IsPrime(a) where a is 2*n^2+30*n+13];
%Y Cf. A142104.
%Y Cf. similar sequences listed in A243888.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Jun 16 2014
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