9,209 research outputs found
Symmetric colorings of polypolyhedra
Polypolyhedra (after R. Lang) are compounds of edge-transitive 1-skeleta.
There are 54 topologically different polypolyhedra, and each has
icosidodecahedral, cuboctahedral, or tetrahedral symmetry, all are realizable
as modular origami models with one module per skeleton edge. Consider a
coloring in which each edge of a given component receives a different color,
and where the coloring (up to global color permutation) is invariant under the
polypolyhedron's symmetry group. On the Five Intersecting Tetrahedra, the edges
of each color form visual bands on the model, and correspond to matchings on
the dodecahedron graph. We count the number of such colorings and give three
proofs. For each of the non-polygon-component polypolyhedra, there is a
corresponding matching coloring, and we count the number of these matching
colorings. For some of the non-polygon-component polypolyhedra, there is a
corresponding visual-band coloring, and we count the number of these band
colorings
Aperiodic colorings and tilings of Coxeter groups
We construct a limit aperiodic coloring of hyperbolic groups. Also we
construct limit strongly aperiodic strictly balanced tilings of the Davis
complex for all Coxeter groups
Coloring Link Diagrams And Conway-type Polynomial Of Braids
In this paper we define and present a simple combinatorial formula for a
3-variable Laurent polynomial invariant of conjugacy classes in Artin braid
group . We show that this Laurent polynomial satisfies the Conway skein
relation and its coefficients are Vassiliev invariants of braids.Comment: This is a revised version. To appear in Topology and its Application
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