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

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Text this: On the operator bk related to the bessel heat equation