set decomposition
Source: miklos schweitzer 1993 q2
October 21, 2021
number theory
Problem Statement
Let A be a subset of natural numbers and let k , r be positive integers. Suppose that for any r different elements selected from A , their greatest common divisor has at most k different prime factors. Prove that A can be partitioned into B and C , where any element of B has at most k + 1 different prime divisors and