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Search: id:A080642
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| A080642 |
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Cube-free taxicab numbers: the smallest cube-free number that is the sum of 2 cubes in n ways. |
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1
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OFFSET
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1,1
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COMMENT
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A necessary condition for the sum to be cube-free is that each pair of cubes be relatively prime.
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EXAMPLE
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2 = 1^3 + 1^3 1729 = 12^3 + 1^3 = 10^3 + 9^3 15170835645 = 2468^3 + 517^3 = 2456^3 + 709^3 = 2152^3 + 1733^3 1801049058342701083 = 1216500^3 + 92227^3 = 1216102^3 + 136635^3 = 1207602^3 + 341995^3 = 1165884^3 + 600259^3
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CROSSREFS
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Cf. A011541.
Sequence in context: A160224 A129061 A011541 this_sequence A108331 A162554 A113917
Adjacent sequences: A080639 A080640 A080641 this_sequence A080643 A080644 A080645
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KEYWORD
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hard,more,nonn
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AUTHOR
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Stuart Gascoigne (Stuart.G(AT)scoigne.com), Feb 28 2003
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