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 _    _     _____     _____      ___      ______  
| |  | ||  |  ___||  |__  //    / _ \\   /_   _// 
| |/\| ||  | ||__      / //    / //\ \\    | ||   
|  /\  ||  | ||__     / //__  |  ___  ||  _| ||   
|_// \_||  |_____||  /_____|| |_||  |_|| /__//    
`-`   `-`  `-----`   `-----`  `-`   `-`  `--`

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Text this: Linear Operators that Preserve the Edgesum of a Graph