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

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Examples

			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)
		

Links

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

Crossrefs

Cf. A001015.

Programs

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