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A325089
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Prime numbers congruent to 49 or 121 modulo 240 representable by x^2 + 150*y^2.
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3
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601, 769, 2281, 2521, 2689, 3001, 5569, 5641, 5881, 6121, 6361, 6529, 6841, 7489, 8209, 8521, 9649, 9721, 11329, 12049, 12289, 12601, 13009, 14281, 14929, 15241, 16369, 17401, 17881, 18289, 19009, 19489, 19801, 20929, 21169, 21481, 21649, 21961, 22129, 22369
(list;
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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COMMENTS
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Brink showed that prime numbers congruent to 49 or 121 modulo 240 are representable by exactly one of the quadratic forms x^2 + 150*y^2 or x^2 + 960*y^2. This sequence corresponds to those representable by the first form, and A325090 corresponds to those representable by the second form.
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LINKS
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EXAMPLE
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Regarding 5881:
- 5881 is a prime number,
- 5881 = 24*240 + 121,
- 5881 = 59^2 + 0*59*4 + 150*4^2,
- hence 5881 belongs to this sequence.
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PROG
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(PARI) See Links section.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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