A003370 Numbers that are the sum of 3 positive 7th powers.

3, 130, 257, 384, 2189, 2316, 2443, 4375, 4502, 6561, 16386, 16513, 16640, 18572, 18699, 20758, 32769, 32896, 34955, 49152, 78127, 78254, 78381, 80313, 80440, 82499, 94510, 94637, 96696, 110893, 156251, 156378, 158437, 172634, 234375, 279938, 280065, 280192, 282124, 282251

Offset

1,1

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Example

From David A. Corneth, Aug 04 2020: (Start)
1320614777 is in the sequence as 1320614777 = 9^7 + 12^7 + 20^7.
5868568576 is in the sequence as 5868568576 = 8^7 + 20^7 + 24^7.
17285710304 is in the sequence as 17285710304 = 3^7 + 12^7 + 29^7. (End)

Prog

(PARI) list(lim)=my(v=List(), x7, t); lim\=1; for(x=1, sqrtnint(lim-2, 7), x7=x^7; for(y=1, min(sqrtnint(lim-x7, 7), x), t=x7+y^7; for(z=1, min(sqrtnint(lim-t, 7), y), listput(v, t+z^7)))); Set(v) \\ Charles R Greathouse IV, Nov 05 2017

Crossrefs

Cf. A001015.

Sequence in context: A097420 A037119 A113558 * A156957 A202030 A048434

Adjacent sequences: A003367 A003368 A003369 * A003371 A003372 A003373

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved