IN the published correspondence of Euler there is a note from him to Goldbach, or, the other way, from Goldbach to Euler, in which a very wonderful theorem is stated which has never been proved by ...

For anyone fascinated by powers and integers, there’s no shortage of problems to tackle, whether by ingenious logic or massive computer search. In 1769, while thinking about the problem now known as ...

The four stamps, issued by China Post, each depicts pi the mathematical constant, the Pythagorean theorem, Euler's formula and Mobius strip. [Photo by Jiang Dong/China Daily] They are enthralled by ...