A063617 Smallest k such that 8^k has exactly n 1's in its decimal representation.

1, 3, 8, 14, 19, 28, 39, 38, 51, 76, 69, 65, 95, 56, 107, 115, 130, 124, 180, 171, 168, 160, 186, 193, 199, 169, 207, 216, 200, 223, 192, 282, 285, 240, 278, 322, 298, 317, 331, 309, 315, 343, 311, 416, 378, 430, 403, 402, 454, 441, 376

Offset

0,2

Links

Table of n, a(n) for n=0..50.

Mathematica

a = {}; Do[k = 1; While[ Count[ IntegerDigits[8^k], 1] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a
Join[{1, 3}, Module[{nn=500, p8}, p8=Table[{n, 8^n}, {n, 0, nn}]; Table[SelectFirst[ p8, DigitCount[#[[2]], 10, 1]==x&], {x, 2, 50}]][[All, 1]]] (* Harvey P. Dale, Sep 06 2022 *)

Crossrefs

Sequence in context: A184517 A028252 A299647 * A062550 A219930 A333962

Adjacent sequences: A063614 A063615 A063616 * A063618 A063619 A063620

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 10 2001

Extensions

Name corrected by Jon E. Schoenfield, Jun 26 2018

Status

approved