There's a famous minority opinion of Rambam that, Biblically, the nidda and zava cycle is continuous--7-11-7-11-7 days ad infinitum, and that most Rishonim argue on him and hold the cycle is 7-11 days (and the next seven days begin with the next period). Chatam Sofer says that Rambam's opinion is rejected in favor of the more accepted opinion (Responsa Yoreh Deah 143; thanks Robert).
Which Rabbis (rishonim and achronim) agree (or partially agree) with Rambam and who completely rejects his opinion?
(I would imagine that because we are dealing with a possible issur kareit the Rambam's position has not been completely rejected).