The expression "n × (n-1)!" represents a mathematical concept related to factorials. Here, "n" is a positive integer, and "(n-1)!" denotes the factorial of (n-1), which is the product of all positive integers from 1 to (n-1). The factorial function is commonly used in combinatorics, probability, and various areas of mathematics. When you multiply "n" by "(n-1)!", you are essentially calculating the factorial of "n," denoted as "n!". This is because "n!" is defined as n × (n-1) × (n-2) × ... × 1, which can also be expressed as n × (n-1)!. This relationship is fundamental in understanding permutations and combinations in mathematics.