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

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Text this: A maximal zero-free interval for chromatic polynomials of bipartite planar graphs