Cameron–Erdős conjecture
In combinatorics, the Cameron–Erdős conjecture is the statement that the number of sum-free sets contained in is
The sum of two odd numbers is even, so a set of odd numbers is always sum-free. There are odd numbers in |N|, and so subsets of odd numbers in |N|. The Cameron–Erdős conjecture says that this counts a constant proportion of the sum-free sets.
The conjecture was stated by Peter Cameron and Paul Erdős in 1988. It was proved by Ben Green and independently by Alexander Sapozhenko in 2003.
