Others are addressing the 'how' of a regex limiting the input to 20 alpha chars. Let me ask 'Why?'

Why are you refusing registration to people with non-[A-za-z] chars in their names and people with long names? What do you want to have happen when the following people try to use your form:

In reply to Re: Stumped by regex by throop
in thread Stumped by regex by brickwall

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