Regular Point
If f is analytic on a domain U, then a point z_0 on the boundary partialU is called regular if f extends to be an analytic function on an open set containing U and also the point z_0 (Krantz 1999, p. 119).
See also
Ordinary PointExplore with Wolfram|Alpha
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References
Krantz, S. G. Handbook of Complex Variables. Boston, MA: Birkhäuser, p. 119, 1999.Referenced on Wolfram|Alpha
Regular PointCite this as:
Weisstein, Eric W. "Regular Point." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/RegularPoint.html