Plane minus a countable set is path connected
ID: plane-minus-a-countable-set-is-path-connected
For a countable set , join two points outside through an auxiliary point avoiding the countably many lines through either endpoint and a point of . Such an auxiliary point exists: choose a line with direction outside the countable list of forbidden directions, then avoid its countably many intersections with those lines. The two segments avoid , giving a continuous path.
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