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

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發送短信 : Primitive substitution tilings with rotational symmetries