Well, it can be done, within certain limits. There is no feature in Limesurvey that allows to create x questions or input fields.
However, what you can do is create a certain number of questions and then hide them based on the numbers requested. I would do it with a dropdown menu, which makes things easier and you can show where the maximum is.
Not 100% what you need, but the only chance I see to do something very similar.
Of course, if the numbers can be huge, this is quite a bad solution. But I assume we are talking about a reasonable number (< 20) and there this should be no problem.
I answer at the LimeSurvey forum in my spare time, I'm not a LimeSurvey GmbH employee.
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