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Safe Keys Combinatorial Lock Design

1925SpecialistCombinatoricsCounting Principles

59. matematično tekmovanje srednješolcev Slovenije

In a company run by several directors, there is a safe locked with six locks. Each director has three keys, each of which opens a different lock. Every key opens exactly one lock. No two directors can open the same three locks, and no two directors together can open the safe. What is the maximum possible number of directors running this company?
0 students attempted0% solvedRating 1925

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