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A134739
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Cubes which are not the sum of three nonzero squares.
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2
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1, 8, 64, 125, 343, 512, 1000, 2197, 3375, 4096, 8000, 12167, 15625, 21952, 29791, 32768, 50653, 59319, 64000, 103823, 140608, 166375, 195112, 216000, 250047, 262144, 357911, 493039, 512000, 614125, 658503, 778688, 857375, 1000000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| This sequence was inspired by e-mail from Ray Chandler, Nov 07 2007
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FORMULA
| a(n) = A004214(n)^3. [From Ray Chandler (rayjchandler(AT)sbcglobal.net), Jan 29 2009]
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EXAMPLE
| 2^3=8 don't have partition on sum of 3 non-zero squares x^2+y^2+z^2 (x,y,z integers)
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MATHEMATICA
| b = Table[x^3, {x, 1, 300}]; a = {}; Do[Do[Do[AppendTo[a, (x^2 + y^2 + z^2)^3], {x, 1, 30}], {y, 1, 30}], {z, 1, 30}]; Union[a]; Complement[b, a] (*Artur Jasinski*)
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CROSSREFS
| Cf. A134738.
Sequence in context: A160428 A074102 A118719 * A116978 A125110 A043152
Adjacent sequences: A134736 A134737 A134738 * A134740 A134741 A134742
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KEYWORD
| nonn
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AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Nov 07 2007
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