The rule is about squares having a certain relationship with their neighbors vs. it is not.
For clarity, rules involving diagonal neighbors or squares more than one step away are never used.
Adjacent-numbered pages: BP1252 BP1253 BP1254 BP1255 BP1256  *  BP1258 BP1259
structure, rules, grid, miniworlds
grid_of_images_with_rule [smaller | same | bigger]
Aaron David Fairbanks