As a reminder, 10 math & computing problems still open: only enigmas #3a and #5 of www.multimagie.com/English/MagicSquaresEnigmasE.pdf are solved. For example, in the following 8x8 "add-mult" example, -when you ADD the numbers, you obtain the same sum for each row, column and diagonal. -when you MULTIPLY the numbers, you obtain the same product for each row, column and diagonal! The first person providing a 7x7 example will win €200 (~$250) + a bottle of champagne. The first person providing a 6x6 example will win €500 (~$620) + a bottle of champagne. The first person providing a 5x5 example will win €1000 (~$1250) + a bottle of champagne. 75 38 207 102 11 20 91 56 5 44 49 104 57 50 153 138 133 200 17 92 45 66 21 26 99 30 39 14 175 152 23 68 78 63 22 15 184 119 100 19 136 161 76 25 42 117 10 33 28 13 40 77 34 69 114 225 46 51 150 171 52 7 88 35 Christian. -----Message d'origine----- De : math-fun-bounces@mailman.xmission.com [mailto:math-fun-bounces@mailman.xmission.com] De la part de James Buddenhagen Envoyé : mercredi 30 mai 2012 21:18 À : math-fun Objet : [math-fun] combinatorial programming contest Since there are clearly wizards here (both mathematicians and programmers) I thought some here might be interested in the just-started programming contest here: http://infinitesearchspace.dyndns.org/ . It is just for fun. The object is to find the largest square grid that can be colored with C colors so that corners of sub-rectangles are not all the same color, and to do this for various values of C (each value a sub-contest). You just register and then start submitting your best results. Since this is somewhat mathematical and for fun, I hope it is not inappropriate to mention here. _______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun