Schubert (1949) showed that every knot can be uniquely decomposed (up to the order in which the decomposition is performed) as a knot sum of a class of knots known as prime knots, which cannot themselves be further decomposed (Livingston 1993, p. 5; Adams 1994, pp.
The Moors were Muslim inhabitants of the Maghreb, the Iberian Peninsula, Sicily, and Malta during the Middle Ages.
In fact, the Moors in Spain had a profound influence not just upon Spain but the whole of Western Europe. Indeed, it has been said that they laid the foundations of the Renaissance that brought Europe out of the intellectual and physical gloom of the Middle Ages.