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A191456
Primes p such that the polynomial x^2+x+p generates only primes for x=1..9.
12
11, 17, 41, 844427, 51448361, 86966771, 122983031, 180078317, 960959381, 1278189947, 1761702947, 1829187287, 2426256797, 2911675511, 3013107257, 4778888351, 5221343711
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..2713
PROG
(PARI) is(n)=for(x=0, 9, if(!isprime(x^2+x+n), return(0))); 1 \\ Charles R Greathouse IV, Sep 14 2015
CROSSREFS
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.
Subsequence such that x=10 gives a composite number: A211238.
Sequence in context: A331940 A187060 A190800 * A146036 A248482 A267772
KEYWORD
nonn
AUTHOR
Zak Seidov, Jun 02 2011
STATUS
approved