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Prime numbers p such that x^2 + x + p produces primes for x = 0..6 but not x = 7.
7

%I #6 Apr 07 2012 19:54:36

%S 1277,28277,113147,421697,665111,1164587,1615631,2798921,2846771,

%T 3053747,5071667,5093507,5344247,5706641,6383051,8396777,10732817,

%U 10812407,11920367,13176587,16197947,16462541,16655447,16943471,17807831,18102101,20488901,23421311

%N Prime numbers p such that x^2 + x + p produces primes for x = 0..6 but not x = 7.

%C The first term is A164926(7).

%H T. D. Noe, <a href="/A210365/b210365.txt">Table of n, a(n) for n = 1..1000</a>

%t lookfor = 7; t = {}; n = 0; While[Length[t] < 30, n++; c = Prime[n]; i = 1; While[PrimeQ[i^2 + i + c], i++]; If[i == lookfor, AppendTo[t, c]]]; t

%Y Cf. A067774, A164926, A210360, A210361, A210362, A210363, A210364.

%K nonn

%O 1,1

%A _T. D. Noe_, Apr 05 2012