OFFSET
0,2
MATHEMATICA
a = {}; Do[k = 1; While[ Count[ IntegerDigits[8^k], 7] != n, k++ ]; a = Append[a, k], {n, 0, 50} ]; a
With[{n8=Table[DigitCount[8^n, 10, 7], {n, 0, 500}]}, Join[{1}, Flatten[ Table[ Position[ n8, i, {1}, 1], {i, 50}]]-1]] (* Harvey P. Dale, Apr 10 2016 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Robert G. Wilson v, Aug 10 2001
EXTENSIONS
Name corrected by Jon E. Schoenfield, Jun 26 2018
STATUS
approved