The case notes
How Renban lines work
The digits on a Renban line form a consecutive set without repeats, in any order. Watch a worked example, then try the idea in a puzzle.
Put it into practice
One consecutive set
This purple path is a Renban line. Its digits form one run of consecutive numbers, without repeats.
3, 4, 5 is the run
Two of these cells already hold three and five. A three-digit run containing both must also contain four.
A run cannot skip 4
If this cell were six, the line would hold three, five and six. It would skip four, so six cannot work.
Any order works
Place four. Reading across the line gives three, five, four. That is fine: a Renban line can scramble the order.
No gaps. No repeats.
Look at the set, not the direction. No gaps and no repeated digits: that is the Renban rule.
Read the transcript
This purple path is a Renban line. Its digits form one run of consecutive numbers, without repeats. Two of these cells already hold three and five. A three-digit run containing both must also contain four. If this cell were six, the line would hold three, five and six. It would skip four, so six cannot work. Place four. Reading across the line gives three, five, four. That is fine: a Renban line can scramble the order. Look at the set, not the direction. No gaps and no repeated digits: that is the Renban rule.
