A063626 Smallest k >= 0 such that 9^k has exactly n 0's in its decimal representation.

0, 5, 11, 41, 33, 38, 42, 27, 60, 71, 63, 85, 94, 139, 96, 127, 157, 166, 131, 160, 170, 148, 190, 210, 212, 203, 221, 222, 218, 257, 223, 243, 250, 275, 302, 255, 273, 271, 333, 372, 270, 339, 371, 457, 408, 347, 402, 410, 483, 448, 355

Offset

0,2

Links

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

Mathematica

a = {}; Do[k = 0; While[ Count[ IntegerDigits[9^k], 0] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a

Prog

(PARI) A063626(n)=for(k=0, oo, #select(d->!d, digits(9^k))==n&&return(k)) \\ M. F. Hasler, Jun 15 2018

Crossrefs

Cf. A031146 (analog for 2^k), A063555 (for 3^k), A063575 (for 4^k), A063585 (for 5^k), A063596 (for 6^k), A063606 (for 7^k), A063616 (for 8^k).

Sequence in context: A212199 A276663 A187984 * A154297 A089441 A046121

Adjacent sequences: A063623 A063624 A063625 * A063627 A063628 A063629

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 10 2001

Extensions

a(0) changed to 0 (as in A031146, A063555, ...) and better title from M. F. Hasler, Jun 15 2018

Status

approved