Pentoads

Pentoads are a type of polyomino, which are geometric shapes composed of squares connected edge-to-edge. A pentomino is a polyomino with five squares. The term "pentoad" specifically refers to a type of pentomino that has a linear or "straight" shape, resembling the letter "I" or a straight line. There are two distinct pentoads: the straight pentomino and the T-shaped pentomino. The straight pentomino is a five-square shape arranged in a single row or column, while the T-shaped pentomino is a five-square shape with a central square connected to four other squares in a T configuration. Pentoads are used in various puzzles and games, including Tetris and pentomino tiling problems. They are also studied in combinatorial geometry and recreational mathematics. The study of pentoads and other polyominoes provides insights into tiling problems, packing problems, and the properties of two-dimensional shapes.