https://en.wikipedia.org/wiki/List_o...etired_numbers
Pretty good history of retired numbers. Also includes comments on numbers that were not officially retired but were also never re-issued by the team to another player (ie. Clemens with the Red Sox and Jim Gantner with the Brewers).
Some teams have retired the same number for multiple players (ie. #31 for the Cubs - Greg Maddux and Fergie Jenkins).