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

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發送短信 : Elementary Number Theory: Primes, Congruences, and Secrets