KöMaL 2016 K509
Nine friends decided to form clubs. Each club will have three members, and any two clubs may have at most one member in common. What is the greatest possible number of clubs they can form?
Official text KöMaL. Quoted with source.
Solutions
No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.
Similar problems
These problems have the most words in common with this statement.