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A063626
Smallest k >= 0 such that 9^k has exactly n 0's in its decimal representation.
6
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
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
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