A063562 Smallest k such that 3^k has exactly n 7's in its decimal representation.

1, 3, 23, 11, 47, 41, 50, 100, 123, 90, 174, 112, 179, 172, 201, 233, 168, 146, 211, 280, 247, 330, 294, 369, 411, 390, 401, 451, 374, 344, 448, 468, 516, 501, 536, 559, 574, 498, 523, 577, 662, 678, 722, 618, 615, 833, 686, 782, 717, 794, 707

Offset

0,2

Links

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

Mathematica

a = {}; Do[k = 1; While[ Count[ IntegerDigits[3^k], 7] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a

Crossrefs

Sequence in context: A285098 A088605 A272816 * A130475 A212998 A157819

Adjacent sequences: A063559 A063560 A063561 * A063563 A063564 A063565

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 10 2001

Extensions

Name corrected by Jon E. Schoenfield, Jun 26 2018

Status

approved