Two articles. 1) In the next issue of Scientific American will be published the English translation of the excellent article of Jean-Paul Delahaye on Sudokus, initially published in French in the December 2005 issue of Pour La Science (see below my old email). 2) And in the next issue of Pour La Science, I will publish an article titled "Les ancêtres français du Sudoku" ("French ancestors of Sudoku") about a forgotten information, even in France: several French newspapers, end XIXth century, published numerous 9x9 grids very close, or using, Sudoku puzzles. Christian. -----Message d'origine----- De : math-fun-bounces+cboyer=club-internet.fr@mailman.xmission.com [mailto:math-fun-bounces+cboyer=club-internet.fr@mailman.xmission.com] De la part de Christian Boyer Envoyé : jeudi 24 novembre 2005 19:51 À : 'math-fun' Objet : [math-fun] Problem Puzzler 1999 Jean-Paul Delahaye publishes in the new issue of Pour La Science a very interesting article on Sudokus. He asked a very strange Sudoku problem WITHOUT any given numbers, only ">" and "<" signs between cells. He mentions that this problem was published in Puzzler, 1999, and that he does not know the solution. I have the solution, sent this morning to J.-P. Delahaye. Now looking for "Puzzler 1999" on Google, I find that Ed Pegg Jr. wrote an article in September 2005 including the same astonishing puzzle, figure 7 "Greater Than Sudoku" in: http://www.maa.org/editorial/mathgames/mathgames_09_05_05.html Perhaps that somebody else had already the solution? Ed, did you receive a solution to your article? Christian. _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun