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A274384
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Numbers n such that 2^n is not the average of three positive cubes.
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0
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1, 2, 4, 5, 7, 8, 10, 11, 13, 14, 16, 17, 19, 20, 22, 23, 25, 26, 28, 29, 31, 32, 34, 37, 40, 43, 46
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OFFSET
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1,2
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COMMENTS
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Numbers n such that 3*2^n = x^3 + y^3 + z^3 where x, y, z > 0, is not soluble.
Numbers n such that A007283(n) is not the sum of three positive cubes.
Sequence is finite because 47, 48, and 49 are not in the sequence and the absence of k from the sequence implies the absence of k+3. - Giovanni Resta, Jun 27 2016
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LINKS
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EXAMPLE
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47 is not a term because 2^47 = (8288^3 + 49808^3 + 66800^3) / 3.
49 is not a term because 2^49 = (13379^3 + 70082^3 + 110309^3) / 3.
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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