A373727 a(n) is the largest number that is the digit sum of an n-digit cube.

8, 10, 18, 28, 28, 44, 46, 54, 63, 73, 80, 82, 98, 100, 109, 118, 125, 136, 144, 154, 154, 163, 172, 181, 190, 190, 199, 208, 217, 226, 235, 243, 253, 260, 262, 278

Offset

1,1

Links

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

Kevin Ryde, C Code

Example

a(7) = 46 because 46 is the largest digital sum encountered among all 7-digit cubes (attained at 3 cubes: 3869893, 7880599, 8998912).

Mathematica

Table[Max@
  Map[Total@IntegerDigits[#^3] &,
   Range[Ceiling@CubeRoot[10^(n - 1)], CubeRoot[10^n - 1]]], {n, 15}]

Prog

(Python)
from sympy import integer_nthroot
def A373727(n): return max(sum(int(d) for d in str(m**3)) for m in range(1+integer_nthroot(10**(n-1)-1, 3)[0], 1+integer_nthroot(10**n-1, 3)[0])) # Chai Wah Wu, Jun 26 2024
(C) /* See links. */

Crossrefs

Cf. A018005, A061439.

Other powers: A371728, A373914, A374025, A373994.

Sequence in context: A143617 A015732 A179474 * A153382 A157911 A090097

Adjacent sequences: A373724 A373725 A373726 * A373728 A373729 A373730

Keyword

nonn,base,more

Author

Zhining Yang, Jun 15 2024

Status

approved