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

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Text this: Nonexistence of a circulant expander family