Notes: In
all
cases one representative set of faces has been highlighted. This
face
remains solid through the various displays in the VRML
window. Pressing the 'frame' hud button will display a
'framework' version of the figure, 'hull' will then display the
figure with a framework convex hull, 'solid' returns to the initial
view.
Structural
Excess Minimum Injective Face-Colourings of Noble Polyhedra with 'O'
(Chiral Octahedral) Symmetry
A
tight 5-colouring is not possible for these 5-valent polyhedra due to
topological parity constraints. When a maximal set of
vertex-disjoint faces possesses 4-fold cyclic symmetry (C4), the 24
faces partition into orbits of 4, requiring a 6-colour arrangement.
sC-2.1
Hull: Snub Cube
Gonality / Valence: 5 / 5
V-E-F: 24-60-24
Genus / Wiener Index: 7 / 806
sC-4.1
Hull: Snub Cube
Gonality / Valence: 5 / 5
V-E-F: 24-60-24
Genus / Wiener Index: 7 / 578
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