Between Line Sudoku: Rules & How to Solve
Every digit on the line lives strictly between the two circled bulbs. Simple to state, sneaky to solve.
The rule
Digits on a between line must fall strictly between the two digits in the circles at its ends. If the bulbs are 2 and 8, the line holds only 3–7.
How to solve between line sudoku
Bulbs define the window
Wide bulbs (like 1 and 9) allow many line values; close bulbs force a narrow, often unique, set.
Count the cells
A long line needs a wide gap between the bulbs — a five-cell line can't sit between 4 and 6.
No equals
Line digits are strictly inside the bulb values, so they never equal either bulb.
Frequently asked questions
- What is a between line in sudoku?
- A line whose digits all fall strictly between the two digits in the circles at its ends.
- Can a between line equal its bulb digits?
- No — the values are strictly between the bulbs, never equal to them.
- How does line length matter?
- Longer lines need a bigger gap between the bulbs to fit enough distinct values.
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