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A140616
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Primes of the form 5x^2+4xy+68y^2.
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2
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5, 101, 173, 269, 293, 461, 509, 677, 773, 797, 941, 1013, 1109, 1181, 1277, 1301, 1613, 1637, 1949, 1973, 2141, 2309, 2357, 2477, 2621, 2693, 2789, 2861, 2957, 3461, 3533, 3701, 3797, 3821, 3989, 4133, 4157, 4373, 4493, 4637, 4877, 4973
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OFFSET
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1,1
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COMMENTS
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Discriminant=-1344. Also primes of the form 5x^2+2xy+101y^2.
In base 12, the sequence is 5, 85, 125, 1X5, 205, 325, 365, 485, 545, 565, 665, 705, 785, 825, 8X5, 905, E25, E45, 1165, 1185, 12X5, 1405, 1445, 1525, 1625, 1685, 1745, 17X5, 1865, 2005, 2065, 2185, 2245, 2265, 2385, 2485, 24X5, 2645, 2725, 2825, 29X5, 2X65, where X is for 10 and E is for 11. Moreover, the discriminant is -940. - Walter Kehowski, May 31 2008
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LINKS
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MATHEMATICA
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Union[QuadPrimes2[5, 4, 68, 10000], QuadPrimes2[5, -4, 68, 10000]] (* see A106856 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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