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A190800 Primes p such that the polynomial x^2 + x + p generates only primes for x = 1..8. 13
11, 17, 41, 844427, 51448361, 51867197, 85776137, 86966771, 93685301, 97122197, 107599757, 113575727, 118136267, 122983031, 180078317, 232728647, 316973621, 483040757, 564537761, 749930717, 840472307, 901288517, 960959381, 1278189947, 1559839991, 1696818647, 1761702947, 1829187287, 2251028567 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Subsequence of A187060: a(1..10)=A187060(1,2,3,7,18,19,26,28,31,32).
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Prime[Range[110*10^6]], AllTrue[Table[x^2+x+#, {x, 8}], PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jul 03 2020 *)
PROG
(PARI) is(n)=for(x=0, 8, if(!isprime(x^2+x+n), return(0))); 1 \\ Charles R Greathouse IV, Sep 14 2015
CROSSREFS
Cf. A187060.
Sequence in context: A144051 A331940 A187060 * A191456 A146036 A248482
KEYWORD
nonn
AUTHOR
Zak Seidov, Jun 02 2011
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)