Marijn Heule turns mathematical statements into something like Sudoku puzzles, then has computers go to work on them. His ...

You'll be more productive if you can see what you need to do, and when you need to do it. This assessment and productivity tool is named for former president Dwight Eisenhower, who once quoted Dr. J.

19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...