Araf (from Turkish, literally "purgatory"; original Japanese name - "Aidabeya") is a logic puzzle. It is played on a rectangular grid. Some of the cells in the grid are numbered. The goal is to divide the grid into regions such that each region contains exactly two numbers. Each region must have an area that is strictly between those numbers. For example, if the region contains 2 and 5, the region's area must be equal to 3 or 4.
Cross+A can solve puzzles from 3 x 3 to 30 x 30.