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

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發送短信 : Green's relations on semigroups of regressive transformations with restricted range