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Search: id:A141302
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| A141302 |
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Primes of the form -x^2+6*x*y+6*y^2 (as well as of the form 11*x^2+18*x*y+6*y^2). |
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8
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| 11, 59, 71, 131, 179, 191, 239, 251, 311, 359, 419, 431, 479, 491, 599, 659, 719, 839, 911, 971
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OFFSET
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0,1
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COMMENT
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Discriminant = 60. Class = 4. Binary quadratic forms a*x^2+b*x*y+c*y^2 have discriminant d=b^2-4ac and gcd(a,b,c)=1
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REFERENCES
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Borevich and Shafaewich, Number Theory.
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EXAMPLE
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a(3)=71 because we can write 71=-1^2+6*1*3+6*3^2 (or 71=11*1^2+18*1*2+6*2^2).
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CROSSREFS
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Cf. A141301, A141303, A141304 (d=60).
Sequence in context: A048366 A107425 A073720 this_sequence A139872 A048524 A142401
Adjacent sequences: A141299 A141300 A141301 this_sequence A141303 A141304 A141305
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KEYWORD
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nonn
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AUTHOR
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Laura Caballero Fernandez, Lourdes Calvo Moguer, Maria Josefa Cano Marquez, Oscar Jesus Falcon Ganfornina and Sergio Garrido Morales (oscfalgan(AT)yahoo.es), Jun 24 2008
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