MathDB
Prime factorisation of n!

Source: ISL 2007 N7

July 13, 2008
modular arithmeticnumber theoryprime factorizationfactorialIMO ShortlistCombinatorial Number Theory

Problem Statement

For a prime p p and a given integer n n let νp(n) \nu_p(n) denote the exponent of p p in the prime factorisation of n! n!. Given dN d \in \mathbb{N} and {p1,p2,,pk} \{p_1,p_2,\ldots,p_k\} a set of k k primes, show that there are infinitely many positive integers n n such that dνpi(n) d\mid \nu_{p_i}(n) for all 1ik 1 \leq i \leq k.
Author: Tejaswi Navilarekkallu, India