159 Kropki
- Kropki dots
The brief
Normal sudoku rules apply.
159: Digits in column 1 indicate the column in which the digit 1 appears in that row (e.g. if r4c1 is a 6, r4c6 is a 1). The same applies to columns 5 and 9, with the digits 5 and 9 respectively.
Kropki: Digits separated by a white dot are consecutive. Digits separated by a black dot have a 2:1 ratio (one is double the other). Not all such dots are shown.