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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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433:Journal of Recreational Mathematics
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638:Juris ČERŅENOKS, Andrejs CIBULIS
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600:Further Questions about Tetrads
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620:Polyomino and Polynar Tetrads
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665:. You can help Knowledge by
484:) solutions, with no holes.
468:Gardner offered a number of
464:Congruent polyform solutions
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636:Tetrads and their Counting
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443:Fewest sides and vertices
369:Nikoli puzzle types
46:Part of a series on
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374:Puzzle video games
359:Impossible puzzles
250:Puzzle video games
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427:is a set of four
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313:Packing problems
308:Optical illusion
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625:A Tetrad Puzzle
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717:Tessellation
667:expanding it
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627:7 April 2020
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544:26 triangles
532:22 triangles
520:10 triangles
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293:Brain teaser
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149:Construction
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268:Metapuzzles
144:Combination
706:Categories
562:References
556:4 hexagons
508:12 squares
496:11 squares
478:polyiamond
328:Puzzlehunt
213:Logic maze
135:Mechanical
121:Logic grid
111:Dissection
474:polyomino
333:Syllogism
236:Crossword
116:Induction
93:Situation
470:polyform
421:geometry
167:problems
79:Guessing
482:polyhex
318:Paradox
298:Dilemma
211: (
198:Sliding
172:Folding
52:Puzzles
480:, and
425:tetrad
284:Topics
241:Sudoku
227:Number
182:Tiling
88:Riddle
657:This
437:holes
352:Lists
259:Mazes
203:Chess
177:Stick
102:Logic
70:Types
663:stub
618:and
423:, a
338:Tale
303:Joke
225:and
223:Word
209:Maze
193:Tour
159:Lock
36:hole
419:In
708::
590:^
570:^
476:,
165:Go
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680:v
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