# Medial tridecagram

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