Ponder This Challenge - February 2026 - Blot-avoiding backgammon strategy
- Ponder This
Ponder This Challenge:
This month's challenge is in honor of the late Professor Solomon Golomb (https://en.wikipedia.org/wiki/Solomon\_W.\_Golomb), who received the National Medal of Science from President Obama on February 2, 2013. Prof. Golomb received his award in the same ceremony as Rangaswamy Srinivasan from IBM, who was awarded his medal for contributions to laser eye surgery.
Golomb proved that any 2^Nx2^N board with a missing square can be tiled with a single r-shaped tromino.
Find at most three types of pentominos (http://mathworld.wolfram.com/Pentomino.html) that can tile every 4^Nx4^N board with a missing square.
Prove your solution.
A high school student (Arthur Befumo) and an IBMer (Jonathan Lenchner) wrote a paper "Extensions of Golomb's Tromino Theorem" (https://fwcg14.cse.uconn.edu/program/wp-content/uploads/sites/863/2014/10/fwcg2014_submission_10.pdf) that solves this month's problem.
Many of you solved with P and Y or P and L. See Jesse Rearick's drawing here on how to solve it with P and L pentominos.