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A260823
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Positive integers that are not divisible by any cube greater than 1 and cannot be written as the sum of two cubes of rational numbers.
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0
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3, 4, 5, 10, 11, 14, 18, 21, 23, 25, 29, 36, 38, 39, 41, 44, 45, 46, 47, 52, 55, 57, 59, 60, 66, 73, 74, 76, 77, 82, 83, 93, 95, 99, 100, 101, 102, 109, 111, 113, 116, 118, 119, 121, 122, 129, 131, 137, 138, 145, 146, 147, 148, 149, 150, 154, 155, 158, 165
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OFFSET
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1,1
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COMMENTS
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This sequence is infinite.
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REFERENCES
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W. Sierpiński, 250 Problems in Elementary Number Theory, 1970, page 112.
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LINKS
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EXAMPLE
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a(4)=10 cannot be written as c^3 + d^3 where both c and d are rational numbers.
22 = (25469/9954)^3 + (17299/9954)^3, so 22 is not in the sequence.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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