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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A383084 The number of points in the Euclidean plane that can be determined via a straightedge-and-compass construction using n or fewer lines and circles.

Original entry on oeis.org

2, 2, 6, 14, 147, 5743, 900487
Offset: 0

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Author

Peter Kagey, Apr 16 2025

Keywords

Examples

			For both n = 0 and n = 1, the a(0) = a(1) = 2 points are the initial points: (0,0) and (1,0).
For n = 2, the a(2) = 6 points are the two above points along with (-1,0), (2,0), (1/2,-sqrt(3)/2), and (1/2,sqrt(3)/2):
  (-1,0): formed by intersecting the line between (0,0) and (1,0) with the circle of radius 1 centered at (0,0).
  (2,0): formed by intersecting the line between (0,0) and (1,0) with the circle of radius 1 centered at (1,0).
  (1/2,-sqrt(3)/2), and (1/2,sqrt(3)/2): formed by intersecting the circle of radius 1 centered at (0,0) with the circle of radius 1 centered at (1,0).
		

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