login
Hints
(Greetings from The On-Line Encyclopedia of Bongard Problems!)
Search: concept:recursion
Displaying 1-10 of 64 results found. ( next )     page 1 2 3 4 5 6 7
     Sort: id      Format: long      Filter: (all | no meta | meta)      Mode: (words | no words)
BP70 There are no side branches of the second order vs. there are side branches of the second order.
(edit; present; nest [left/right]; search; history)
REFERENCE

M. M. Bongard, Pattern Recognition, Spartan Books, 1970, p. 237.

CROSSREFS

Adjacent-numbered pages:
BP65 BP66 BP67 BP68 BP69  *  BP71 BP72 BP73 BP74 BP75

KEYWORD

nice, finished, traditional, bongard

CONCEPT recursion_number (info | search),
recursion (info | search),
tracing_line_or_curve (info | search),
trunk_of_tree (info | search),
two (info | search)

WORLD

curve_tree [smaller | same | bigger]
zoom in left (curve_tree_one_level)

AUTHOR

Mikhail M. Bongard

BP71 There are inside figures of the second order vs. there are no inside figures of the second order.
(edit; present; nest [left/right]; search; history)
REFERENCE

M. M. Bongard, Pattern Recognition, Spartan Books, 1970, p. 237.

CROSSREFS

See BP1022 for a Problem about presence of nesting.

Adjacent-numbered pages:
BP66 BP67 BP68 BP69 BP70  *  BP72 BP73 BP74 BP75 BP76

KEYWORD

nice, finished, traditional, bongard

CONCEPT recursion_number (info | search),
inside (info | search),
recursion (info | search),
two (info | search)

WORLD

[smaller | same | bigger]

AUTHOR

Mikhail M. Bongard

BP167 Every cluster has two clusters of dots vs. every cluster has three clusters of dots.
(edit; present; nest [left/right]; search; history)
CROSSREFS

Adjacent-numbered pages:
BP162 BP163 BP164 BP165 BP166  *  BP168 BP169 BP170 BP171 BP172

KEYWORD

traditional

CONCEPT number (info | search),
dot (info | search),
recursion (info | search),
feature_cluster (info | search),
cluster_of_one (info | search),
cluster (info | search),
two (info | search),
three (info | search)

WORLD

Multiple options:
dot_clusters [smaller | same | bigger],
point_clusters [smaller | same | bigger]

AUTHOR

Harry E. Foundalis

BP186 Object made of objects vs. object made of objects made of objects.
(edit; present; nest [left/right]; search; history)
CROSSREFS

Adjacent-numbered pages:
BP181 BP182 BP183 BP184 BP185  *  BP187 BP188 BP189 BP190 BP191

KEYWORD

traditional

CONCEPT recursion (info | search),
cluster (info | search)

AUTHOR

Harry E. Foundalis

BP188 Shape of whole different from shape of parts vs. shape of whole same as shape of parts.
(edit; present; nest [left/right]; search; history)
CROSSREFS

See BP1002 for more general visual self-similarity.

See BP1064 for a similar Problem about two shapes inter-referencing instead of just one shape referencing itself.

Adjacent-numbered pages:
BP183 BP184 BP185 BP186 BP187  *  BP189 BP190 BP191 BP192 BP193

KEYWORD

traditional

CONCEPT recursion (info | search),
self-reference (info | search),
similar_shape (info | search),
similar (info | search)

AUTHOR

Harry E. Foundalis

BP322 One outer outline vs. more than one outer outline.
(edit; present; nest [left/right]; search; history)
CROSSREFS

Adjacent-numbered pages:
BP317 BP318 BP319 BP320 BP321  *  BP323 BP324 BP325 BP326 BP327

KEYWORD

nice, precise, allsorted, traditional

CONCEPT separated_regions (info | search),
interior_exterior (info | search),
outer_outline (info | search),
recursion (info | search),
one (info | search)

WORLD

nest_shapes [smaller | same | bigger]

AUTHOR

Aaron David Fairbanks

BP344 Shape can tile itself vs. shape cannot tile itself.
(edit; present; nest [left/right]; search; history)
COMMENTS

Left examples are sometimes called "rep-tiles."


The tiles all must be the same size. More specifically, all left examples can tile themselves only using scaled down and rotated versions of themselves with all tiles the same size. Right examples cannot tile themselves using scaled down rotated versions of themselves or even reflected versions of themselves with all tiles the same size.


Without the puzzle piece-like shape EX4120 on the right side the current examples also allow the solution "shape can tile with itself so as to create a parallelogram vs. shape cannot tile with itself so as to create a parallelogram."

CROSSREFS

See BP532 for a version with fractals.

Adjacent-numbered pages:
BP339 BP340 BP341 BP342 BP343  *  BP345 BP346 BP347 BP348 BP349

EXAMPLE

Go to https://oebp.org/files/yet.png for an illustration of how some left-sorted shapes tile themselves.

KEYWORD

hard, nice, precise, notso, unstable, math, hardsort, creativeexamples, proofsrequired, perfect, traditional

CONCEPT recursion (info | search),
self-reference (info | search),
tiling (info | search),
imagined_shape (info | search),
imagined_entity (info | search)

WORLD

shape [smaller | same | bigger]

AUTHOR

Aaron David Fairbanks

BP531 Fractal is tiled by three smaller copies of itself vs. fractal is tiled by five smaller copies of itself.
(edit; present; nest [left/right]; search; history)
COMMENTS

More specifically, all left examples shown in this Problem have Hausdorff dimension log2(3) while all right examples have Hausdorff dimension log3(5).


Left examples can tile themselves by any power of 3 smaller same-sized copies of themselves while right examples can tile themselves by any power of 5 smaller same-sized copies of themselves.


Homage to Bongard's original three versus five Problems.

CROSSREFS

Adjacent-numbered pages:
BP526 BP527 BP528 BP529 BP530  *  BP532 BP533 BP534 BP535 BP536

KEYWORD

perfect, infinitedetail

CONCEPT fractal (info | search),
recursion (info | search),
self-reference (info | search),
tiling (info | search),
three (info | search),
five (info | search)

WORLD

fractal_self_tile [smaller | same | bigger]

AUTHOR

Aaron David Fairbanks

BP532 Self-tiling fractal using one size of tile vs. does not tile itself with a single size of itself.
(edit; present; nest [left/right]; search; history)
CROSSREFS

This is BP344 ("rep-tiles") but for fractals.

See BP1119 for the version with multiple different sizes of tile allowed.

Adjacent-numbered pages:
BP527 BP528 BP529 BP530 BP531  *  BP533 BP534 BP535 BP536 BP537

KEYWORD

hardsort, proofsrequired, perfect, infinitedetail, contributepairs

CONCEPT fractal (info | search),
recursion (info | search),
self-reference (info | search),
tiling (info | search)

WORLD

[smaller | same | bigger]
zoom in left (fractal_self_tile)

AUTHOR

Aaron David Fairbanks

BP533 Contains smaller copy of itself vs. doesn't.
(edit; present; nest [left/right]; search; history)
COMMENTS

A smaller copy of EX6409 (the black area) can be located within itself, but some of the white space inside it is not retained in this smaller copy.

CROSSREFS

Adjacent-numbered pages:
BP528 BP529 BP530 BP531 BP532  *  BP534 BP535 BP536 BP537 BP538

KEYWORD

nice, perfect, infinitedetail, contributepairs

CONCEPT fractal (info | search),
recursion (info | search),
self-reference (info | search)

WORLD

connected_built_from_self_tile_fractals [smaller | same | bigger]

AUTHOR

Aaron David Fairbanks

( next )     page 1 2 3 4 5 6 7

Welcome | Solve | Browse | Lookup | Recent | Links | Register | Contact
Contribute | Keywords | Concepts | Worlds | Ambiguities | Transformations | Invalid Problems | Style Guide | Goals | Glossary