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%I #11 Sep 08 2022 08:46:08
%S 71,107,191,239,347,1031,1439,1667,1787,2039,2447,2591,3371,3539,5231,
%T 5651,5867,6311,7247,9311,9587,10151,11027,11939,12251,14207,14891,
%U 19727,20939,21767,23039,27539,30431,34511,36107,39971,41687,46439,47051,56039,56711
%N Primes of the form 2*n^2+26*n+11.
%C Subsequence of A068231.
%C Conjecture: except 107, 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
%C 2*a(n) + 147 is a square. - _Vincenzo Librandi_, Apr 10 2015
%H Vincenzo Librandi, <a href="/A243888/b243888.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Table[2 n^2 + 26 n + 11, {n, 800}], PrimeQ]
%o (Magma) [a: n in [1..200] | IsPrime(a) where a is 2*n^2+26*n+11];
%Y Cf. A068231.
%Y Cf. Primes of the form 2*n^2+2*(2*k+3)*n+(2*k+1): A176549 (k=0), A221902 (k=1), A154577 (k=2), A154592 (k=3), A154601 (k=4), this sequence (k=5), A243889 (k=6), A217494 (k=7), A243890 (k=8), A221903 (k=9), A217495 (k=10), A217496 (k=11), A217497 (k=12), A217498 (k=13), A243891 (k=14), A243957 (k=15), A217499 (k=16), A217500 (k=17), A217501 (k=18), A217620 (k=19), A243958 (k=20), A217621 (k=21).
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Jun 16 2014
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