In the book Физико-математические этюды с Mathcad и Интернет , by the way, mentioned by many mathematicians - Russian and foreign. The most mentioned was "Russian-foreign" mathematician, physicist, engineer, astronomer and philosopher Leonhard Euler. He was born in Switzerland (1707), but he has worked for many years and was buried (1783) in St. Petersburg. At the time of the work on the second edition of the book I was in town Riehen close to Basel, where Euler spent his youth and where Euler in his honor, a memorial plaque.
I stood at this memorial sign, remembering math book challenges associated with Euler: the rope formula wound on the pole (p. 141), the method of solving ordinary differential equations (page 222.), The image of the set method using circles (page 265), number theory (p. 338), graph theory (p. 346), shipbuilding theory (study 23), etc. this relief Euler is remarkable in that it is encrypted (see sketch 3.) the name of the great mathematician - Leonard ( "persistent, brave lion "). Sculptor so designed Euler hair, it can be seen that the profile of this king of beasts.
Do you know something about this "Euler-Lion-code"? Only me is visible this lion?
More (but without a lion) - http://www.w-volk.de/museum/plaque10.htm
