Chua’s circuit is the simplest electronic circuit that produces chaos—the output of this circuit never repeats the same sequence, and is a truly random signal. If you need a good source of randomness, ...

Author’s note: This article shows how to derive circuit gain equations via a signal flow graph. With practice you may be able to write a gain equation by locating signal paths and loops in the ...

Antimagic labelling is a fascinating area of graph theory that assigns unique integers to the edges of a graph in such a way that the resulting vertex sums are distinct. This concept, grounded in the ...

On March 15, intriguing seminar announcements sent rumblings through the field of combinatorics, the mathematical study of counting. Three collaborators planned to give coordinated talks the following ...

Two computer scientists found — in the unlikeliest of places — just the idea they needed to make a big leap in graph theory. This past October, as Jacob Holm and Eva Rotenberg were thumbing through a ...

When you get stuck on a fiendishly difficult sudoku, it’s hard not to wonder if the puzzle really has a solution. At another moment, aglow in the triumph of a clever deduction, you might have a ...