A063635 Smallest k such that 9^k has exactly n 9's in its decimal representation.

2, 1, 5, 15, 25, 18, 41, 56, 51, 69, 66, 102, 87, 137, 88, 116, 100, 117, 135, 151, 129, 110, 190, 139, 187, 210, 236, 253, 218, 261, 264, 257, 301, 318, 312, 303, 285, 335, 291, 337, 300, 310, 384, 351, 390, 362, 374, 405, 413, 435, 436

Offset

0,1

Links

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

Mathematica

a = {}; Do[k = 1; While[ Count[ IntegerDigits[9^k], 9] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a
Module[{nn=500, tbl}, tbl=Table[{n, DigitCount[9^n, 10, 9]}, {n, nn}]; Table[SelectFirst[ tbl, #[[2]] == k&], {k, 0, 50}]][[All, 1]] (* Harvey P. Dale, Jan 06 2023 *)

Crossrefs

Sequence in context: A144237 A350742 A268295 * A192264 A144054 A144058

Adjacent sequences: A063632 A063633 A063634 * A063636 A063637 A063638

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 10 2001

Extensions

Name corrected by Jon E. Schoenfield, Jun 26 2018

Status

approved