Problem #PRU-100489

Problems Number Theory Divisibility Products and factorials The fundamental theorm of arithmetic. Prime factorisation.

Problem

Let us introduce the notation – we denote the product of all natural numbers from 1 to \(n\) by \(n!\). For example, \(5!=1\times2\times3\times4\times5=120\).

a) Prove that the product of any three consecutive natural numbers is divisible by \(3!=6\).

b) What about the product of any four consecutive natural numbers? Is it always divisible by 4!=24?