FindRepeat

FindRepeat[list] finds the minimal sublist or subarray that repeats to give list.

FindRepeat[list,n] requires that the sublist be repeated at least n times in list.

FindRepeat[list,{n1,n2,…}] requires ni to repeat at level i in list.

FindRepeat["string"] finds the minimal substring that repeats to give string.

FindRepeat["string",n] requires that the substring be repeated at least n times.

Examples

Find the repeating pattern in a list:

FindRepeat[{a, b, a, b, a, b}]
(* {a, b} *)

Find the repeating substring:

FindRepeat["abcabcabc"]
(* "abc" *)

Please visit the official Wolfram Language Reference for more details.