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  _  _      ___      _  __   __   __    ______  
 | \| ||   / _ \\   | |/ //  \ \\/ //  /_   _// 
 |  ' ||  | / \ ||  | ' //    \ ` //     | ||   
 | .  ||  | \_/ ||  | . \\     | ||     _| ||   
 |_|\_||   \___//   |_|\_\\    |_||    /__//    
 `-` -`    `---`    `-` --`    `-`'    `--`

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發送短信 : Primitive substitution tilings with rotational symmetries