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The solutions with four congruent tiles include some with five sides. However, their placement surrounds an uncovered hole in the plane. Among solutions without holes, the ones with the fewest possible sides are given by a hexagon identified by Scott Kim as a student at
Stanford University. It is not
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Kim's solution has 16 vertices, while some of the pentagon solutions have as few as 11 vertices. It is not known whether fewer vertices are possible.
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disjoint planar regions in the plane, each pair sharing a finite portion of common boundary. It was named by
Michael R. W. Buckley in 1975 in the
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Application of IT in
Mathematical Proofs and in Checking of Results of Pupils’ Research
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known whether five-sided solutions without holes are possible.
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Tetrad with one central region and 3 surrounding ones
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428:Journal of Recreational Mathematics
660:. You can help Knowledge (XXG) by
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576:Penrose Tiles to Trapdoor ciphers
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633:Juris ČERŅENOKS, Andrejs CIBULIS
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595:Further Questions about Tetrads
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615:Polyomino and Polynar Tetrads
479:) solutions, with no holes.
463:Gardner offered a number of
459:Congruent polyform solutions
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631:Tetrads and their Counting
434:, other enclosed regions.
438:Fewest sides and vertices
364:Nikoli puzzle types
46:Part of a series on
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369:Puzzle video games
354:Impossible puzzles
250:Puzzle video games
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308:Optical illusion
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712:Tessellation
662:expanding it
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622:7 April 2020
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539:26 triangles
527:22 triangles
515:10 triangles
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293:Brain teaser
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149:Construction
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268:Metapuzzles
144:Combination
701:Categories
557:References
551:4 hexagons
503:12 squares
491:11 squares
473:polyiamond
328:Puzzlehunt
213:Logic maze
135:Mechanical
121:Logic grid
111:Dissection
469:polyomino
333:Syllogism
236:Crossword
116:Induction
93:Situation
465:polyform
416:geometry
167:problems
79:Guessing
477:polyhex
318:Paradox
298:Dilemma
211: (
198:Sliding
172:Folding
52:Puzzles
475:, and
420:tetrad
284:Topics
241:Sudoku
227:Number
182:Tiling
88:Riddle
652:This
432:holes
347:Lists
259:Mazes
203:Chess
177:Stick
102:Logic
70:Types
658:stub
613:and
418:, a
303:Joke
225:and
223:Word
209:Maze
193:Tour
159:Lock
36:hole
414:In
703::
585:^
565:^
471:,
165:Go
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