Heptagram

Regular heptagram (7/2)
A regular heptagram
Type	Regular star polygon
Edges and vertices	7
Schläfli symbol	{7/2}
Coxeter diagram
Symmetry group	Dihedral (D7)
Internal angle (degrees)	≈77.143°
Dual polygon	self
Properties	star, cyclic, equilateral, isogonal, isotoxal

Regular heptagram (7/3)
A regular heptagram
Type	Regular star polygon
Edges and vertices	7
Schläfli symbol	{7/3}
Coxeter diagram
Symmetry group	Dihedral (D7)
Internal angle (degrees)	≈25.714°
Dual polygon	self
Properties	star, cyclic, equilateral, isogonal, isotoxal

A heptagram, septagram, or septegram is a seven-point star drawn with seven straight strokes.

The name heptagram combines a numeral prefix, hepta-, with the Greek suffix . The -gram suffix derives from γραμμῆς (grammēs) meaning a line.

In general, a heptagram is any self-intersecting heptagon (7-sided polygon).

There are two regular heptagrams, labeled as {7/2} and {7/3}, with the second number representing the vertex interval step from a regular heptagon, {7/1}.

This is the smallest star polygon that can be drawn in two forms, as irreducible fractions. The two heptagrams are sometimes called the heptagram (for {7/2}) and the great heptagram (for {7/3}).

The previous one, the regular hexagram {6/2}, is a compound of two triangles. The smallest star polygon is the {5/2} pentagram.

The next one is the {8/3} octagram, followed by the regular enneagram, which also has two forms: {9/2} and {9/4}, as well as one compound of three triangles {9/3}.

Former Georgian coat of arms, 1918–1921, 1991–2004

Roundel of the Georgian Air Force

Flag of Cherokee Nation

The seven-pointed star of the Felibritge on the Occitan flag.

The Jordanian flag, bearing the star that symbolizes Al-Fatiha

Logo of Maersk

Symbol of Hokkaido

Bibliography

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Wikipedia