Source taken from Wikipedia.org
Kenichi: The Mightiest Disciple (Shijō Saikyō no Deshi Ken'ichi?, lit. History's Strongest Disciple Kenichi) is a Japanese manga by Syun Matsuena serialized in the weekly manga magazine Shōnen Sunday. The first tankōbon was published in August 9, 2002. An anime adaptation by Tokyo Movie Shinsha aired from October 2006 to September 2007.
This manga is a remake of Tatakae! Ryōzanpaku Shijō Saikyō no Deshi (Fight! Ryōzanpaku, History's Strongest Disciple), which was serialized in the monthly manga magazine Shōnen Sunday Super, publishing five tankōbon between 2000 and 2002.