Tetragram

Lachlan's term for a set of four lines, no three of which are concurrent.

See also

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References

Lachlan, R. "Properties of a Tetragram." §147-155 in An Elementary Treatise on Modern Pure Geometry. London: Macmillian, pp. 90-97, 1893.

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Cite this as:

Weisstein, Eric W. "Tetragram." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Tetragram.html

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