Note that, based on that definition, if the first and last characters are the same, then the answer is "the string minus the last character". Which leads to: 

/^(.+?).*\1$/

[download]

Which leads to a full solution of: 

/^((.*?).*?)\2*\1$/

[download]

which might be horribly inefficient (at least for some cases) or might not; I haven't considered it.

- tye        

In reply to Re^3: Finding repeat sequences. (only regex) by tye
in thread Finding repeat sequences. by BrowserUk

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