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Primes p such that the polynomial x^2+x+p generates only primes for x=1..11.
8

%I #23 Sep 14 2015 14:28:24

%S 17,41,1761702947,8776320587,10102729577,11085833111,177558051107,

%T 273373448057,473787509537,557149355507,715464238661,1359854730821,

%U 2131528031441,2170341748697,2236159108277,2308235320997,2751203698151,3247566894821,3288002848511,3424305123047

%N Primes p such that the polynomial x^2+x+p generates only primes for x=1..11.

%C Subsequence of A191457.

%C The sequence is infinite under Dickson's conjecture. - _Charles R Greathouse IV_, Oct 11 2011

%H Charles R Greathouse IV and Zak Seidov, <a href="/A191458/b191458.txt">Table of n, a(n) for n = 1..79</a>

%o (PARI) is(n)=for(x=0,11, if(!isprime(x^2+x+n), return(0))); 1 \\ _Charles R Greathouse IV_, Sep 14 2015

%Y Cf. A187060, A190800, A191456, A191457.

%K nonn

%O 1,1

%A _Zak Seidov_, Jun 02 2011

%E a(12)-a(20) from _Charles R Greathouse IV_, Oct 17 2011