2 The She'iltoth (questions) of Rab Alai (8th century) also belong probably to the school of Pumbeditha, though their author was not Gaon.
High plateaus like that of Pamir (the " Roof of the World ") and Armenia, and lofty mountain chains like the snow-clad Caucasus, the Alai, the Tian-shan, the Sayan Mountains, exist only on the outskirts of the empire.
The Alai range of the Pamir, continued by the Kokshaltau range and the Khan-tengri group of the Tian-shan, and the Sailughem range of the Altai, which is continued in the unnamed border-range of West Sayan (between the Bei-kem and the Us), belong to this category.
The border-ridges of the Alai Mountains, the Khantengri group, the Sailughem range and the West Sayan contain the highest peaks of their respective regions.
+(m -3) D 5(213) (214) (15) - (13) (14) (14), as= and and we see further that (alai +a2a2+...+amam) k vanishes identically unless (mod m).