https://en.m.wikipedia.org/wiki/Polyomino "The 18 one-sided pentominoes, including 6 mirrored pairs, Without the 6 mirrored pairs." https://numberblocks.fandom.com/wiki/
https://scratch.mit.edu/discuss/youtube/KPffpuHYIhc/ 0:35 or 2:35 or 3:06 or 3:48
