A059094 Numbers whose sum of digits is a cube.

1, 8, 10, 17, 26, 35, 44, 53, 62, 71, 80, 100, 107, 116, 125, 134, 143, 152, 161, 170, 206, 215, 224, 233, 242, 251, 260, 305, 314, 323, 332, 341, 350, 404, 413, 422, 431, 440, 503, 512, 521, 530, 602, 611, 620, 701, 710, 800, 999, 1000, 1007, 1016, 1025

Offset: 1

Author

Enoch Haga, Feb 13 2001

Keywords

• easy
• nonn
• base

Comments

The first occurrence of a new cube value in sequence 1, 8, 27, 64, ... occurs at a great distance from each previous value.

Consecutive terms differ by 1 iff they are of the form 999..999 and 1000..000 provided the number of 9s is 3*(u^3): that is 999 (length 3) whose digit sum is 27=3^3; 99..99 (length 24) whose digitsum is 216=6^3; 99.999 (length 81) whose digitsum is 729=9^3. - Carmine Suriano, Mar 31 2014

Examples

			999 has digit sum 9 + 9 + 9 = 27 = 3^3, so 999 is a term.
		

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..10000 (first 390 terms from Carmine Suriano)

Crossrefs

Cf. A007953.

Programs

Mathematica

Select[Range[1000], IntegerQ@ Power[Total@ IntegerDigits[#], 1/3] &] (* Michael De Vlieger, Jul 16 2022 *)

PARI

isok(n) = ispower(sumdigits(n), 3); \\ Michel Marcus, Jun 06 2014