# Medial tridecagram

Medial tridecagram Rank2
TypeRegular
SpaceSpherical
Notation
Bowers style acronymMat
Coxeter diagramx13/4o
Schläfli symbol{13/4}
Elements
Edges13
Vertices13
Measures (edge length 1)
Circumradius$\frac{1}{2\sin\frac{4\pi}{13}} ≈ 0.60755$ Inradius$\frac{1}{2\tan\frac{4\pi}{13}} ≈ 0.34513$ Area$\frac{13}{4\tan\frac{4\pi}{13}} ≈ 2.24331$ Angle$\frac{5\pi}{13} ≈ 69.23077^\circ$ Central density4
Number of external pieces26
Level of complexity2
Related polytopes
ArmyTad, edge length $\frac{\sin\frac{\pi}{13}}{\sin\frac{4\pi}{13}}$ DualMedial tridecagram
ConjugatesTridecagon, Small tridecagram, Tridecagram, Great tridecagram, Grand tridecagram
Convex coreTridecagon
Abstract & topological properties
Flag count26
Euler characteristic0
OrientableYes
Properties
SymmetryI2(13), order 26
ConvexNo
NatureTame

The medial tridecagram is a non-convex polygon with 13 sides. It's created by taking the third stellation of a tridecagon. A regular medial tridecagram has equal sides and equal angles.

It is one of five regular 13-sided star polygons, the other four being the small tridecagram, the tridecagram, the great tridecagram, and the grand tridecagram.