Step puzzles
Fill the staircase so every row and column follows its rule. Few clues, one answer.
- Fill every empty circle so the numbers along each line, every row and every column, form an arithmetic sequence. Lines turn green when they work and red when they don’t. Negative numbers are allowed.
Strategy: find a line with two known numbers. If they are j steps apart, the common difference is their gap divided by j. Fill in that line, and the new numbers unlock the lines that cross it.
On the staircases all numbers are positive, and one- or two-cell lines follow any rule automatically. Arrow keys move between cells.