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

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發送短信 : On primitive Pythagorian triples using a geoboard