Heptagon

The unconstructible regular seven-sided Polygon, illustrated above, has Schläfli Symbol .

Although the regular heptagon is not a Constructible Polygon, Dixon (1991) gives several close approximations. While theAngle subtended by a side is , Dixon gives constructions containing angles of, , and.

Madachy (1979) illustrates how to construct a heptagon by folding and knotting a strip of paper.

References

Courant, R. and Robbins, H. ``The Regular Heptagon.'' §3.3.4 in What is Mathematics?: An Elementary Approach to Ideas and Methods, 2nd ed. Oxford, England: Oxford University Press, pp. 138-139, 1996.

Dixon, R. Mathographics. New York: Dover, pp. 35-40, 1991.

Madachy, J. S. Madachy's Mathematical Recreations. New York: Dover, pp. 59-61, 1979.

• Sierpinski's Theorem
• Sierpinski Tetrahedron
• Sierpinski Triangle
• Sieve
• Sieve of Eratosthenes
• Sievert Integral
• Sievert's Surface
• Sifting Property
• Sigma Algebra
• Sigma Function
• Sigmoid Curve
• Sigmoid Function
• Sign
• Signalizer Functor Theorem
• Signature (Knot)
• Signature (Quadratic Form)
• Signature (Recurrence Relation)
• Signature Sequence
• Signed Deviation
• Significance
• Significance Test
• Significant Digits
• Significant Figures
• Signpost
• Signum