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A139992 Primes of the form 20x^2+20xy+47y^2. 1
47, 167, 383, 503, 647, 887, 983, 1223, 1487, 1823, 1847, 2063, 2663, 2687, 2903, 3023, 3167, 3407, 3527, 3863, 4007, 4583, 4703, 5087, 5927, 6047, 6263, 6863, 7103, 7607, 7703, 7727, 8447, 8543, 8783, 9623, 9743, 9887, 10223, 10247, 10463 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-3360. See A139827 for more information.

Also primes of the forms 47x^2+40xy+80y^2 and 47x^2+42xy+63y^2. See A140633. - T. D. Noe (noe(AT)sspectra.com), May 19 2008

FORMULA

The primes are congruent to {47, 143, 167, 383, 503, 647} (mod 840).

MATHEMATICA

QuadPrimes[20, -20, 47, 10000] (* see A106856 *)

CROSSREFS

Sequence in context: A185938 A132251 A078857 * A142916 A204610 A158632

Adjacent sequences:  A139989 A139990 A139991 * A139993 A139994 A139995

KEYWORD

nonn,easy

AUTHOR

T. D. Noe (noe(AT)sspectra.com), May 02 2008

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Last modified February 16 06:18 EST 2012. Contains 205860 sequences.