A379869 a(n) is the least number whose cube is an n-digit cube which has the maximum sum of digits (A373727(n)).

2, 4, 9, 19, 31, 92, 157, 423, 927, 1966, 4289, 8782, 12599, 30355, 99829, 215083, 341075, 989353, 2131842, 4081435, 8334082, 20632999, 43967926, 88316866, 190349299, 364929616, 735501679, 1948602829, 3036548692, 9654499999, 17087193298, 31037622999, 99594689449, 181610950229, 426932901019, 956829383603

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Example

For n=7, the maximum sum of digits for a 7-digit cube is A373727(7) = 46 and this is attained by 3 cubes, the smallest of which is 157^3 = 3869893 so that a(7) = 157.

Mathematica

Table[t =SortBy[Map[{#, Total@IntegerDigits[#^3]} &,
    Range[Ceiling@CubeRoot[10^(n - 1)], CubeRoot[10^n - 1]]], Last];
 Select[t, #[[2]] == t[[-1]][[2]] &][[1, 1]], {n, 18}]

Prog

(C) /* See A373727. */

Crossrefs

Cf. A373727, A380052.

Other powers: A380111, A379650, A380567.

Sequence in context: A283877 A331850 A373808 * A391787 A081490 A292478

Adjacent sequences: A379866 A379867 A379868 * A379870 A379871 A379872

Keyword

nonn,base

Author

Zhining Yang, Jan 11 2025

Extensions

a(26) and a(35) corrected by Kevin Ryde, Apr 03 2025

Status

approved