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mathematics "Einstein Tile" mystery solved: amateur mathematician discovers unique 13-sided "hat" Mark Frauenfelder
mathematics This "Weird Units Calculator" can convert watts into T-Rex bites and lightsabers Thom Dunn
mathematics New research: There's a 50-50 chance we're living in a simulation and here's how to find out David Pescovitz
math Weird and wild warped-grid jigsaw puzzles inspired by Mobius, Haeckel, and Picasso David Pescovitz
NASA Katherine Johnson, pioneering NASA mathematician portrayed in "Hidden Figures," RIP David Pescovitz