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A027755 Primes of the form k^2 + k + 5. 8

%I

%S 5,7,11,17,47,61,137,277,311,347,467,557,761,997,1061,1487,1811,2357,

%T 2657,3911,4561,5261,5407,5857,6011,6977,7487,8377,8747,9511,11777,

%U 12437,13577,14767,16007,17827,18637,18911,21467,23567,25127

%N Primes of the form k^2 + k + 5.

%C a(5) through a(14) are identical to the first 10 values of q, the left-hand column of "Example 2.3. We give examples of maximal and minimal elliptic curves over finite fields over F_q with discriminant -19 for all q < 1000", p. 4, and "Example 5.2. We produce examples of optimal curves over finite fields with discriminant -19" pp. 10-11 of E. Alekseenko, et al. - _Jonathan Vos Post_, Feb 12 2009

%H Seiichi Manyama, <a href="/A027755/b027755.txt">Table of n, a(n) for n = 1..10000</a>

%H E. Alekseenko, S. Aleshnikov, N. Markin and A. Zaytsev, <a href="http://arxiv.org/abs/0902.1901">Optimal Curves of Genus 3 over Finite Fields with Discriminant -19</a>, arXiv:0902.1901 [math.AG], 2009-2011. [_Jonathan Vos Post_, Feb 12 2009]

%H P. De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>

%F a(n) = A027754(n)^2 + A027754(n) + 5. - _Seiichi Manyama_, Mar 19 2017

%t nn = Range[0, 200]; Select[nn^2 + nn + 5, PrimeQ] (* _Jean-Fran├žois Alcover_, Nov 17 2018 *)

%o (MAGMA) [a: n in [0..250]|IsPrime(a) where a is n^2+n+5] // _Vincenzo Librandi_, Dec 20 2010

%Y Cf. A014556, A027754.

%K nonn

%O 1,1

%A _Patrick De Geest_

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Last modified April 21 19:16 EDT 2021. Contains 343156 sequences. (Running on oeis4.)