Volume XXXII


Geombinatorics Quarterly

Issue 1  (July 2022)

A Finite Graph Approach to the Probabilistic Hadwiger-Nelson Problem

by Haydn Gwyn, Jacob Stavrianos 5

On the Babai and upper chromatic numbers of Rn with non-Euclidean distance

by William Jones and Jakub Kraus 29

No Repeated Slopes, Triangles and Polygons

by Shakhar Smorodinsky and Charles Wolf 40

Popularizing History: Karl-Friedrich Bonhoeffer and His Friends, A Review of “The Scientific World of Karl- Friedrich Bonhoeffer: The Entanglement of Science, Religion, and Politics” by Kathleen L. Housley

by Alexander Soifer 48

Issue 2  (October 2022)

Tiling the plane with hexagons: improved separations for k-colourings


by Aubrey D.N.J DeGrey and Jaan Parts 57
On lower bounds of the order of k-chromatic unit distance graphs by Aubrey D.N.J DeGrey and Jaan Parts 72
A Generalization of Szlam's Lemma by Alan Li, Amelia Shapiro, and Kaylee Weatherspoon 75
Maximal Tilings with the Minimal Tile Property  by Iwan Praton 82
There is no censorship in the Western World, or is there? An essay in six movements by Alexander Soifer 87

Issue 3  (January 2023)

Grid dissections of tangential quadrilaterals


by Erica Choi, Dan Ismailescu, Jiho Lee, and Joonsoo Lee 101
Saturated Sets of Distinct Integer Equilateral
by Erich Friedman and James Tilley 117
Aperiodic Sets of Prototiles Extracted from the
Penrose Rhomb Tiling
by Mike Winkler 122
Pragmatism beats Historicism in our day and age by  Alexander Soifer 132

Issue 4 (April 2023)

A 5-chromatic same-distance graph in the hyperbolic plane


by Geoffrey Exoo, Dan Ismailescu 145
More certainty in coloring the plane with a forbidden distance interval… by by Jaan Parts 159
Nesting Parallelepipeds, A Minimax Problem by Alexander Soifer 186