login
Hints
(Greetings from
The On-Line Encyclopedia of Bongard Problems
!)
BP421
Allocated for user.
(
edit
;
present
;
nest
[
left
/
right
];
search
;
history
)
CROSSREFS
Adjacent-numbered pages:
BP416
BP417
BP418
BP419
BP420
*
BP422
BP423
BP424
BP425
BP426
Welcome
|
Solve
|
Browse
|
Lookup
|
Recent
|
Links
|
Register
|
Contact
Contribute
|
Keywords
|
Concepts
|
Worlds
|
Ambiguities
|
Transformations
|
Invalid Problems
|
Style Guide
|
Goals
|
Glossary