The History of No Neighbors
A modern logic puzzle from Japan with one simple twist: equal digits keep their distance.
An Inventor's Puzzle
No Neighbors was invented by the Japanese puzzle designer Naoki Inaba, who published it in 2001. Inaba has created a great many logic puzzles, often built on a single clear rule that leads to surprisingly deep reasoning.
The puzzle combines two familiar ideas: regions that must each hold a fixed set of digits, as in Sudoku's boxes, and a neighbourhood rule borrowed from the king in chess - a digit may not repeat anywhere a king could step to.
Under Other Names
Outside Japan the puzzle appears under other names as well, for example as Suguru or as Tectonic. The rules are the same everywhere; PaperGames uses the inventor's original name.
Every puzzle here is created fresh on your device: blocks and a valid solution are built together cell by cell, then digits are removed one at a time for as long as a built-in solver still finds exactly one solution.