# Small tridecagram

Small tridecagram
Rank2
TypeRegular
Notation
Bowers style acronymSat
Coxeter diagramx13/2o ()
Schläfli symbol{13/2}
Elements
Edges13
Vertices13
Measures (edge length 1)
Circumradius${\displaystyle {\frac {1}{2\sin {\frac {2\pi }{13}}}}\approx 1.07510}$
Inradius${\displaystyle {\frac {1}{2\tan {\frac {2\pi }{13}}}}\approx 0.95267}$
Area${\displaystyle {\frac {13}{4\tan {\frac {2\pi }{13}}}}\approx 6.19236}$
Angle${\displaystyle {\frac {9\pi }{13}}\approx 124.61538^{\circ }}$
Central density2
Number of external pieces26
Level of complexity2
Related polytopes
ArmyTad, edge length ${\displaystyle {\frac {1}{2\cos {\frac {\pi }{13}}}}}$
DualSmall tridecagram
ConjugatesTridecagon, Tridecagram, Medial tridecagram, Great tridecagram, Grand tridecagram
Convex coreTridecagon
Abstract & topological properties
Flag count22
Euler characteristic0
OrientableYes
Properties
SymmetryI2(13), order 26
Flag orbits1
ConvexNo
NatureTame

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

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