Volume XVIII


Geombinatorics Quarterly

July 2008 (Volume XVIII, Issue 1)

[4,3]-Configurations with Many Symmetries By Branko Grünbaum 5
Note on Covering Square with Equal Squares By Dmytro Karabash and Alexander Soifer 13
Rational Trigonometry: Computational Viewpoint By Olga Kosheleva 18
Equidecomposability (Scissors Congruence) of Polyhedra in R3 and R4 is Algorithmically decidable: Hilbert’s 3rd Problem Revisited By Vladik Krienovich 26
Reflective Polyhedra By Zsolt Lengvarszky 35

October 2008 (Volume XVIII, Issue 2)

On the chromatic number of real and rational spaces By Josef Cibulka 53
A note on Convex Realizability of Arrangements of Pseudocircles By Johann Linhart and Ronald Ortner 66
Tromino Tiling Deficient Cubes of Side Length 2n By Norton Starr 72
Book Reviews    
There is More to Coloring than Colors, a review of Alexander Soifer’s “Mathematical Coloring Book” By Branko Grünbaum 88
Review of Alexander Soifer’s “mathematical Coloring Book” By Peter D. Johnson, Jr 91

January 2009 (Volume XVIII, Issue 3)

Untangle: Knots in Combinatorial Game Theory By Sandy Ganzell and Alex Meadows 101
Vertex-to-Vertex Packings of Congruent Regular Polygons By Heiko Harborth 109
Points in a Triangle Forcing Small Triangles By Matthew Kahle 114
On Graphs that Cannot be Represented by Linked Compact Sets By Aleksandr Kuz’minykh 129
Book Reviews    
Encyclopedia of Graph Coloring and the Story of its Creation: An Easy in Five Parts, a review of G. Chartrand and P. Zhang’s book “Chromatic Graph Theory By Alexander Soifer 135
Letters to the Editor By Johann Linhart and Ronald Ortner 141

April 2009 (Volume XVIII, Issue 4)

Explicit Colorings of Z3 and Z4 with Four Colors to Forbid Arbitrary Distances By Jeffery Burkert 149
Small Unstretchable Simplicial Arrangements of Pseudolines By Branko Grünbaum 153
Which Pairs of Distances can be Forbidden by a 4-Coloring of Q3? By Peter Johnson and Michael Tiemeyer 161
A New Proof of the Sylvester-Gallai Theorem By Johnathan Lenchner 171
Tiling a Deficient Board by P-Pentonimoes By Catalin Nitica and Viorel Nitika 175
A Note on Sum of Squared Distances between Vertices of a Convex Polygon By Pavel Novotný 185
Book Reviews    
 “A Thing of Beauty a Joy For Ever,” A review of John H. Conway, Heidi Burgiel and Chaim Goodman-Strauss’s book “The Symmetries of Things” By Alexander Soifer 187