3,153 reputation
1034
bio website mathpuzzle.com
location Champaign, IL
age 50
visits member for 3 years, 1 month
seen 14 hours ago

I run the site mathpuzzle, and used to be the main advisor for the TV show Numb3rs. I've contributed extensively to MathWorld. Before that, I wrote the Math Games columns for the MAA. I am now the chief editor for the Wolfram Demonstrations Project. Of my own Demonstrations there, some of my favorites are: - Mrs. Perkins's Quilts - Tightly Packed Squares - Social Golfer Problem - The Circles Of Descartes - Triangle Calculator


Jul
12
awarded  Revival
Jul
10
accepted What is the smallest number of $45^\circ-60^\circ-75^\circ$ triangles that a square can be divided into?
Jul
2
awarded  Curious
Jun
11
asked Fusible numbers — can we prove fuse(4) is finite?
Jun
11
asked Famous graphs with nice 3D embeddings
Jun
10
awarded  Yearling
Jun
6
comment Is a “nice” plane tiling possible where each tile has 7 (8, 9, …) neighbors?
See also mathworld.wolfram.com/TruncatedIcosahedralGraph.html Those are sphere mappings. You need to have one polygon on the outside. from its vertices, you connect to the vertices of polygons on the inner part that expose 2 sides. With Heptagons, you'll always have outer polygons with three sides exposed.
Jun
3
comment Is a “nice” plane tiling possible where each tile has 7 (8, 9, …) neighbors?
For that image from the hyperbolic heptagon tiling, you'll have an outer area with a lot of polygons that don't touch at least 7 others.
Jun
3
answered Is a “nice” plane tiling possible where each tile has 7 (8, 9, …) neighbors?
Jun
3
accepted Is 292229292292 the longest 29-smooth number made of 2's and 9's?
Jun
3
comment Is 292229292292 the longest 29-smooth number made of 2's and 9's?
A short, elegant proof is likely impossible, so "highly unlikely, here's why" is good enough.
Jun
2
comment How to defend Mathematics from “ignorant” people?
In such situations, talk about money. Ask them to give you all of their money. Hand them back a fraction of what they gave you. If they refuse, or object, then you've proved that they do like math. Otherwise, pocket the money -- they are a hopeless case, and you are richer for it.
Jun
2
asked Is 292229292292 the longest 29-smooth number made of 2's and 9's?
Mar
20
answered tetrahedron height
Mar
20
revised Prove that Petersen's graph is non-planar using Euler's formula
edited body
Mar
20
revised Prove that Petersen's graph is non-planar using Euler's formula
deleted 137 characters in body
Mar
20
answered Prove that Petersen's graph is non-planar using Euler's formula
Mar
19
answered What are the simple Heesch-2 polyforms?
Feb
17
awarded  Revival
Feb
17
revised Is there any hope to disprove goldbach's conjecture?
deleted 4 characters in body