A063594 Smallest k such that 5^k has exactly n 9's in its decimal representation.

1, 8, 17, 23, 58, 59, 40, 57, 74, 92, 93, 114, 112, 143, 155, 156, 160, 193, 113, 195, 212, 214, 215, 236, 216, 287, 291, 295, 309, 289, 288, 360, 274, 371, 427, 418, 444, 462, 478, 464, 466, 494, 530, 545, 482, 561, 481, 597, 644, 689, 650

Offset

0,2

Links

Harry J. Smith, Table of n, a(n) for n = 0..150

Mathematica

a = {}; Do[k = 1; While[ Count[ IntegerDigits[5^k], 9] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a

Prog

(PARI) a(n)={my(k=1); while(n<>#select(d->d==9, digits(5^k)), k++); k} \\ Harry J. Smith, Aug 26 2009, Andrew Howroyd, Jun 26 2018

Crossrefs

Sequence in context: A088488 A031458 A044991 * A110474 A118066 A044060

Adjacent sequences: A063591 A063592 A063593 * A063595 A063596 A063597

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 10 2001

Extensions

Name corrected by Jon E. Schoenfield, Jun 25 2018

Status

approved