Punctured Plane
The complex plane C with the origin removed, i.e., C-{0}. The punctured plane is sometimes denoted C^* (although this notation conflicts with that for the Riemann sphere C-*, or extended complex plane). It is both a Lie group and an Abelian variety.
See also
C-*, Complex Plane, Punctured Set, Riemann SphereExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Punctured Plane." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/PuncturedPlane.html