An aperiodic set of 11 Wang tiles

A [Wang tile](https://en.wikipedia.org/wiki/Wang_tile) is a square tile such that each of its edges colored. The plane can be _tiled_ with set Wang tiles if contained in the placed without rotations and reflections whole covered colors their match at adjacent tiles. were introduced by [Wang](https://en.wikipedia.org/wiki/Hao_Wang_(academic)) 1961 to study decidability mathematical logic, they are also relevance other areas theoretical computer science. conjectured tiled tiles, then it periodic way. This was refuted [Berger](https://en.wikipedia.org/wiki/Robert_Berger_(mathematician)) 1966 who described how Turing machine computation emulated tilings constructed 104 for which but only aperiodically. In first volume [The Art Computer Programming](https://en.wikipedia.org/wiki/The_Art_of_Computer_Programming), Knuth presented simplified version Berger's 92 Smaller sets aperiodically subsequently smallest containing 13 found Culik II 1996. authors construct 11 colored four tiling aperiodic. Moreover, establish there no most 10 this property. number best possible as known every three either periodically or cannot all.