Anraikumozaiku ("Unlike Mosaic") is a logic puzzle invented by Naoki Inaba (Japan). A rectangular or square grid contains circles in some cells. The goal is to divide the grid into rectangular regions. Each region contains one circle. Black cells do not belong to any region. Regions of the same size must not share an edge.
Cross+A can solve puzzles from 3 x 3 to 30 x 30.