Identity theorem for Riemann surfaces

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In mathematics, the identity theorem for Riemann surfaces is a theorem that states that a holomorphic function is completely determined by its values on any subset of its domain that has a limit point.

Statement of the theorem

Let and be Riemann surfaces, let be connected, and let be holomorphic. Suppose that for some subset that has a limit point, where denotes the restriction of to . Then (on the whole of ).

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