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A024981
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Numbers that are the sum of 3 positive cubes, including repetitions.
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3
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3, 10, 17, 24, 29, 36, 43, 55, 62, 66, 73, 80, 81, 92, 99, 118, 127, 129, 134, 136, 141, 153, 155, 160, 179, 190, 192, 197, 216, 218, 225, 232, 244, 251, 251, 253, 258, 270, 277, 281, 288, 307, 314, 342, 344, 345, 349, 352, 359, 368, 371, 375, 378, 397, 405, 408, 415, 433
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OFFSET
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1,1
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REFERENCES
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H. Davenport, Sums of three positive cubes, J. London Math. Soc., 25 (1950), 339-343. Coll. Works III p. 999.
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LINKS
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EXAMPLE
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An example of repetition: 251 shows twice, because 251 = 1^3+5^3+5^3 = 2^3+3^3+6^3. [Jean-François Alcover, Jul 31 2013]
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MATHEMATICA
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m = 8; Sort[Select[Flatten[Table[x^3 + y^3 + z^3, {x, 1, m}, {y, x, m}, {z, y, m}]], # <= m^3 + 2 &]] (* T. D. Noe, Jul 30 2013 *)
max = 500; pr = Table[ PowersRepresentations[n, 3, 3], {n, 1, max}] // Flatten[#, 1]& // Select[#, Times @@ # != 0 &]&; Total[#^3] & /@ pr (* Jean-François Alcover, Jul 31 2013 - replaced my previous incorrect code *)
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CROSSREFS
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KEYWORD
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nonn,easy,nice
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AUTHOR
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EXTENSIONS
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Inserted a second 251 from T. D. Noe, Jul 30 2013
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STATUS
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approved
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