From the people behind the Alan Turing Cryptography Competition.
You are reading the website of the 2019 edition of the MathsBombe Competition, which ended on Sunday 28th April at 11:59 pm

# Puzzle 8

You select a set $$A=\{A_1,...,A_N\}$$ of N different integers from the range 1 to 24. What is the minimum value of N such that for any choice of A there are two disjoint subsets of A with the same sum? Find also all selections A of size N-1 for which the sums of each subset are all different.