Reptiles are known for polyominoes, polyiamonds, polyaboloes, and other polyforms.
Few polyforms of any kind form reptiles. A bireptile is a figure of which copies can be joined to form two joined, equally enlarged copies of the original figure.
Any figure with a reptiling trivially has a bireptiling, but not every figure with a bireptiling has a reptiling. That is, bireptiles are more common than reptiles.
Below I show minimal known bireptilings for various polyominoes.
| Number of Cells | Number of Reptiles | Number
of Bireptiles |
|---|---|---|
| 1 | 1 | 1 |
| 2 | 1 | 1 |
| 3 | 2 | 2 |
| 4 | 4 | 4 |
| 5 | 4 | 4 |
| 6 | 10 | 11 |
| 7 | 6 | 6 |
| 8 | 12 | 16 |
| 9 | 41 | 41 |
| 10 | 28 | 35 |
Last revised 2015-12-10.