Watch Your Step
- Indexing lines
The brief
- Normal sudoku rules apply, i.e. each row, column, and 3x3 region has to contain the digits from 1 to 9 once each.
- Periodic Sums: A clue outside the grid indicates the sum of N and every Nth digit in the row or column, where N is the digit in the first cell seen from the clue. (For example, if there is a 16 clue to the left of Row 5 and r5c1 is a 3, then r5c1, r5c4, and r5c7 must sum to 16.)
- Index Lines: Each turquoise line is an Index Line, i.e. the digit in the Nth cell along such a line (starting from the diamond) indicates the position along the line where the digit N appears. For example, if a diamond cell contains a 3, the third cell along that line must have a 1.