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

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Text this: Symmetry groups of single-wall nanotubes