Abu'l-Qasim al-Tayyib
Abū'l-Qāsim al-Ṭayyib ibn al-Āmir (أبو القاسم الطيب بن الآمر) was, according to the Tayyibi sect of Isma'ilism, the twenty-first imam. The only son of Caliph al-Amir bi-Ahkam Allah, al-Tayyib was an infant when his father was murdered.