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Search: id:A141176
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| A141176 |
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Primes of the form 2*x^2+3*x*y-3*y^2 (as well as of the form 6*x^2+9*x*y+2*y^2). |
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7
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| 2, 11, 17, 29, 41, 83, 101, 107, 131, 149, 167, 173, 197, 227, 233, 239, 263, 281, 293, 347, 359, 431, 461, 479, 491, 503, 557, 563, 569, 593, 659, 677, 701, 743, 761, 809, 821, 827, 857, 887, 941, 953
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OFFSET
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1,1
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COMMENT
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Discriminant = 33. Class = 2. 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.
D. B. Zagier, Zetafunktionen und quadratische Koerper.
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EXAMPLE
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a(3)=17 because we can write 17=2*4^2+3*4*5-3*5^2 (or 17=6*1^2+9*1*1+2*1^2)
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CROSSREFS
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Cf. A141177 (d=33) A038872 (d=5). A141131 (d=8). A141122, A141123 (d=12). A038883 (d=13). A038889 (d=17): A141111, A141112 (d=65).
Sequence in context: A164368 A104272 A117155 this_sequence A118839 A091735 A106949
Adjacent sequences: A141173 A141174 A141175 this_sequence A141177 A141178 A141179
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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 (marcanmar(AT)alum.us.es), Jun 12 2008
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