Erdős number
The Erdős number (Hungarian: [ˈɛrdøːʃ]) describes the "collaborative distance" between mathematician Paul Erdős and another person, as measured by authorship of mathematical papers. The same principle
Erdős–Bacon number
A person's Erdős–Bacon number is the sum of one's Erdős number—which measures the "collaborative distance" in authoring academic papers between that person and Hungarian mathematician Paul Erdős—and o
Morphy number
The Morphy number is a measure of how closely a chess player is connected to Paul Morphy (1837–1884) by way of playing chess games.
Six Degrees of Kevin Bacon
Six Degrees of Kevin Bacon or Bacon's Law is a parlor game where players challenge each other to arbitrarily choose an actor and then connect them to another actor via a film that both actors have app