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Named after Hungarian mathematician Paul Erdős.
Etymology from Wiktionary, CC BY-SA 4.0.
Erdős number
Today it means: A number describing the degree of collaboration between a mathematician and Paul Erdős, defined such that a mathematician who has written a paper with Erdős has an Erdős number of 1, a mathematician who has written a paper with somebody having an Erdős number of 1 has an Erdős number of two, and so on. Full definition →