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EnA Bulgarian created the most difficult Sudoku in the world. The manager of the Bulgarian castle in Ravadinovo Yanko Krastev improved the record from 2012 of the Finnish mathematician Arto Inkala. The [...]
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A Bulgarian created the most difficult Sudoku in the world. The manager of the Bulgarian castle in Ravadinovo Yanko Krastev improved the record from 2012 of the Finnish mathematician Arto Inkala. The [...]
Read More