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  ______     ___      _____      ___      _  __  
 /_   _//   / _ \\   / ____||   / _ \\   | |/ // 
 `-| |,-   | / \ || / //---`'  | / \ ||  | ' //  
   | ||    | \_/ || \ \\___    | \_/ ||  | . \\  
   |_||     \___//   \_____||   \___//   |_|\_\\ 
   `-`'     `---`     `----`    `---`    `-` --`

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發送短信 : Enumeration of index 3 and 4 subgroups of hyperbolic triangle symmetry groups