**Leonhard Euler** (1707-1783) was one of the greatest mathematicians of all time, one whose stature may be compared to that of Galileo, Newton, and Einstein. April 15, 2007, marked the 300th anniversary of Euler's birth, which is being celebrated in events around the world.

In his book *A Concise History of Mathematics*, Dirk Struik wrote of Euler: "The life of this eighteenth century academician was almost exclusively devoted to work in the different fields of pure and applied mathematics. Although he lost one eye in 1735 and the other eye in 1766, nothing could interrupt his enormous productivity. The blind Euler, aided by a phenomenal memory, continued to dictate his discoveries. During his life 560 books and papers appeared; at his death he left many manuscripts, which were published by the St. Petersburg Academy during the next forty-seven years... He made signal contributions in every field of mathematics which existed in his day."

The article about Euler at the MacTutor History of Mathematics web site provides further details about his life and achievements. A biography written by Emil A. Fellman, a historian at the University of Basel (Switzerland) and an authority on Euler, was published this year in English translation by Birkhäuser. The same publisher has also brought out a comic book about the life of Euler, *Ein Mann, mit dem man rechnen kann* , which was recently published in English as *Euler, A Man to Be Reckoned With*. The AMS has published *Euler Through Time: A New Look at Old Themes*, by V.S. Varadarajan. In 1999, the Mathematical Association of America published *Euler The Master of Us All,* by William Dunham; an informative and enthusiastic review by Ed Sandifer appears on the MAA web site.

Euler was born in Basel and lived and worked for many years in St. Petersburg, and those two cities are the sites of major conferences marking the anniversary of his birth. The International Euler Symposium was held in Basel on May 30 and June 1, 2007, just one event in a larger, months-long celebration in that city. The Leonhard Euler Festival took place June 10-12, 2007, in St. Petersburg, which also held other celebratory events during the months of May and June. A one-day meeting of the British Society for the History of Mathematics, Euler's Mathematical Legacy, took place on June 30, 2007, at the University of Oxford. This is just a small sampling of the activities worldwide.

To top all this off, a mathematics problem, dubbed the *Euler Conjecture*, has been proposed by A. A. Mullin of Madison, Alabama. For the statement of the conjecture, go to the web site of the March 2007 issue of the *London Mathematical Society Newsletter* and look under the "Meetings" section.

The October 2007 issue of the *Bulletin of the American Mathematical Society* is dedicated to Euler, and includes the following:

*Articles* :

- Euler and his work on infinite series, by Veeravalli S. Varadarajan

- Euler and algebraic geometry, by Burt Totaro

- Euler's
*De partitio Numerorum*, by George Andrews - Euler's definition of the derivative, by Harold Edwards
- The Euler equations for compressible fluid flow, by Demetrios Christodoulou

- On the Euler equations of incompressible fluids, by Peter Constantin

*Mathematical Perspectives section* :

- What is good mathematics?, by Terence Tao
- About the cover, by Gerald Alexanderson
- Selections reprinted from
*Mathematical Reviews,*by C. J. Scriba

For more information on Leonhard Euler, visit

- The Euler Archive
- Eric Weisstein's World of Science
- The Math Forum: Leonhard Euler and the Bridges of Konigsberg
- The Math Forum: Ask Dr. Math FAQ: About
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---*Allyn Jackson *