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%I A191456 #20 Dec 04 2021 12:28:11
%S A191456 11,17,41,844427,51448361,86966771,122983031,180078317,960959381,
%T A191456 1278189947,1761702947,1829187287,2426256797,2911675511,3013107257,
%U A191456 4778888351,5221343711
%N A191456 Primes p such that the polynomial x^2+x+p generates only primes for x=1..9.
%H A191456 Charles R Greathouse IV, <a href="/A191456/b191456.txt">Table of n, a(n) for n = 1..2713</a>
%o A191456 (PARI) is(n)=for(x=0,9, if(!isprime(x^2+x+n), return(0))); 1 \\ _Charles R Greathouse IV_, Sep 14 2015
%Y A191456 Generates primes for x=1..k: A001359 (1), A022004 (2), A172454 (3), A187057 (4), A187058 (5), A144051 (6), A187060 (7), A190800 (8), this sequence (9), A191457 (10), A191458 (11), A253592 (12), A253605 (13). Each is by definition a subsequence of preceding sequences.
%Y A191456 Subsequence such that x=10 gives a composite number: A211238.
%Y A191456 Cf. A160548, A164926.
%K A191456 nonn
%O A191456 1,1
%A A191456 _Zak Seidov_, Jun 02 2011

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