OFFSET
1,7
EXAMPLE
The 12th squarefree number is 17, with binary expansion (1,0,0,0,1), so a(12) = 3.
MAPLE
MATHEMATICA
DigitCount[Select[Range[100], SquareFreeQ], 2, 0]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Gus Wiseman, May 09 2024
STATUS
approved