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           _    _      _____     ___     ______   
    ___   | || | ||   / ___//   / _ \\  |      \\ 
   /   || | || | ||   \___ \\  / //\ \\ |  --  // 
  | [] || | \\_/ ||   /    // |  ___  |||  --  \\ 
   \__ ||  \____//   /____//  |_||  |_|||______// 
    -|_||   `---`   `-----`   `-`   `-` `------`  
     `-`

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發送短信 : Colorings of Hyperbolic Plane Crystallographic Patterns