Grinberg Formula
A formula satisfied by all Hamiltonian Circuits with 
nodes. Let 
be the numberof regions inside the circuit with 
sides, and let 
be the number of regions outside the circuit with sides.If there are 
interior diagonals, then there must be 
regions
 | (1) |
sides is bounded by Edges, so such regions contribute 
to the total. However, this countseach diagonal twice (and each Edge only once). Therefore, | (2) |
(1), | (3) |
 | (4) |
 | (5) |
- Semiregular Polyhedron
- Semiring
- Andrews-Curtis Link
- Andrews-Schur Identity
- Andrew's Sine
- Andrica's Conjecture
- André's Problem
- André's Reflection Method
- Anger Function
- Angle
- Angle Bisector
- Angle Bisector Theorem
- Angle Bracket
- Angle of Parallelism
- Angle Trisection
- Angular Acceleration
- Angular Defect
- Angular Distance
- Angular Velocity
- Anharmonic Ratio
- Anisohedral Tiling
- Annihilator
- Annulus
- Annulus Conjecture
- Annulus Theorem