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A274384 Numbers n such that 2^n is not the average of three positive cubes. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..27.

EXAMPLE

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.

CROSSREFS

Cf. A000079, A003072, A007283.

Sequence in context: A059564 A001651 A224999 * A195175 A248607 A191266

Adjacent sequences:  A274381 A274382 A274383 * A274385 A274386 A274387

KEYWORD

nonn,fini,full

AUTHOR

Altug Alkan, Jun 19 2016

STATUS

approved

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Last modified May 25 01:17 EDT 2019. Contains 323534 sequences. (Running on oeis4.)