Sevener

al-Ismāʿīliyya al-khāliṣa / al-Ismāʿīliyya al-wāqifa or Seveners () was a branch of Ismā'īlī Shīʻa. They became known as "Seveners" because they believed that Isma'il ibn Jafar was the seventh and the last Imam (hereditary leader of the Muslim community in the direct line of Ali). They believed his son, Muhammad ibn Isma'il, would return and bring about an age of justice as Mahdi. Their most famous and active branch were the Qarmatians.
List of Imams.
Sometimes "Sevener" is used to refer to Ismā'īlīs overall, though mainstream Musta'li and Nizari Isma'ilis have far more than seven imams.
Ismaili imams who were not accepted as legitimate by Seveners.
The following Ismaili imams after Mahdi had been considered as heretics of dubious origins by certain Qarmatian groups who refused to acknowledge the imamate of the Fatimids and clung to their belief in the coming of the Mahdi.