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Primes p such that the polynomial x^2+x+p generates only primes for x=1..10.
7

%I #17 Jan 06 2015 04:59:39

%S 17,41,180078317,1278189947,1761702947,1829187287,5862143447,

%T 6369321857,7226006861,8776320587,10102729577,11085833111,12412643261,

%U 50626299797,53039299211,72355485857,74621287901,76233413141,81948881447,115826556611,129077263697

%N Primes p such that the polynomial x^2+x+p generates only primes for x=1..10.

%C Dickson's conjecture implies that this sequence is infinite. [_Charles R Greathouse IV_, Jun 03 2011]

%H Zak Seidov, <a href="/A191457/b191457.txt">Table of n, a(n) for n = 1..464</a>

%o (PARI) isokp(p) = {for (n=1, 10, if (! isprime(subst(x^2+x+p, x, n)), return (0));); 1;}

%o lista(nn) = {forprime (p=1, nn, if (isokp(p), print1(p, ", ")); ); } \\ _Michel Marcus_, Jan 05 2015

%Y Subsequence of A191456. Cf. A187060, A190800.

%K nonn

%O 1,1

%A _Zak Seidov_, Jun 02 2011