NestList
NestList[f, expr, n] gives a list of the results of applying f to expr 0 through n times.
Example: NestList[f, x, 3]. NestList[f, expr, n] gives a list of length n + 1. See The Mathematica Book on the web: Section 2.2.2. See also: Nest, NestWhileList, FoldList, ComposeList.
Further Examples
NestList[f, expr, n] gives a list of the results of applying f to expr 0 through n times. 
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