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A135791
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Positive numbers of the form x^5-10x^3*y^2+5x*y^4 (where x,y are integers and x>y).
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6
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404, 1900, 3647, 5646, 12928, 13412, 14050, 27688, 30609, 36413, 45716, 51804, 60800, 74576, 90050, 98172
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| See A135792, union A135791 and A135792 see A135793. Squares of these numbers are of the form N^5-M^2 (where N belongs to A135787 and M to A057102) Proof uses: (x^5-10x^3 y^2+5xy^4)^2=(x^2+y^2)^5-(5x^4y-10x^2y^3+y^5)^2. [This line needs editing! - N. J. A. Sloane (njas(AT)research.att.com), Dec 04 2007]
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MATHEMATICA
| a = {}; Do[Do[w = x^5 - 10x^3 y^2 + 5x y^4; If[w > 0 && w < 100000, AppendTo[a, w]], {x, y, 1000}], {y, 1, 1000}]; Union[a]
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CROSSREFS
| Cf. A000404, A050803, A057102, A135784, A060803, A135786, A135787, A135789, A135790, A135792, A135793.
Sequence in context: A117836 A185640 A185637 * A187382 A185638 A198536
Adjacent sequences: A135788 A135789 A135790 * A135792 A135793 A135794
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KEYWORD
| nonn
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AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Nov 29 2007
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