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How a Strange Grid Reveals Hidden Connections Between Simple Numbers
A graduate student has helped illuminate a long-suspected connection between addition and multiplication.
A Child’s Puzzle Has Helped Unlock the Secrets of Magnetism
People have known about magnets since ancient times, but the physics of ferromagnetism remains a mystery. Now a familiar puzzle is getting physicists closer to the answer.
Unscrambling the Hidden Secrets of Superpermutations
A science fiction novelist and an internet commenter made breakthroughs on a longstanding problem about the number of ways you can arrange a set of items. What did they discover?
Mystery Math Whiz and Novelist Advance Permutation Problem
A new proof from the Australian science fiction writer Greg Egan and a 2011 proof anonymously posted online are now being hailed as significant advances on a puzzle mathematicians have been studying for at least 25 years.
Four Is Not Enough
How many colors do you need to color an infinite plane so that no points 1 unit apart are the same color?
Decades-Old Graph Problem Yields to Amateur Mathematician
By making the first progress on the “chromatic number of the plane” problem in over 60 years, an anti-aging pundit has achieved mathematical immortality.
The (Math) Problem With Pentagons
Triangles fit effortlessly together, as do squares. When it comes to pentagons, what gives?
A Mathematician Who Dances to the Joys and Sorrows of Discovery
Federico Ardila opens up about his journey as a mathematician, teacher, Colombian transplant, DJ and creator of mathematical spaces.
Marjorie Rice’s Secret Pentagons
A California housewife who in the 1970s discovered four new types of tessellating pentagons is dead at 94.