Odd number of enclosed regions vs. even number of enclosed regions.
The use of numbers and pictures are only a distraction.
See BP966 for the version in which the background counts.
Odd number of enclosed region vs. even number of enclosed regions.
odd number of enclosed region VS even number of enclosed regions
The use of numbers and pictures are only a distraction
Thomas Joyce
See BP891 for version with nesting allowed.
Bongard Problems with world non-nesting, non-intersecting triangle and circle outlines vs. other Bongard Problems
Bongard Problems with world triangle and circle outlines vs. other Bongard Problems
They are not allowed to intersect.
Aaron David Fairbanks