Erdős number facts for kids
The Erdős number (IPA: [ɛrdøːʃ]) honors the Hungarian mathematician Paul Erdős. Erdős was one of the most prolific mathematical writers. He worked with many mathematicians.
Paul Erdős's number is 0. Anyone who directly worked with Paul Erdős has an Erdős number of 1. Anyone who works with those collaborators who have an Erdős number of 1, has an Erdős number of 2. The chain continues like that.
Related pages
 Jerry Grossman, The Erdös Number Project. Contains statistics and a complete list of all mathematicians with an Erdős number less than or equal to 2.
Images for kids

Paul Erdős in 1992

If Alice collaborates with Paul Erdős on one paper, and with Bob on another, but Bob never collaborates with Erdős himself, then Alice is given an Erdős number of 1 and Bob is given an Erdős number of 2, as he is two steps from Erdős.

Paul Erdős in 1985 at the University of Adelaide teaching Terence Tao, who was then 10 years old. Tao became a math professor at UCLA, received the Fields Medal in 2006, and was elected a Fellow of the Royal Society in 2007. His Erdős number is 2