New Zealand Maths Olympiad Committee online

After a marathon final session that spent over two hours on a single script, we finally completed co-ordination at about 7:15 this evening. We were the very last team to do so. We’re extremely happy with how the team have done: their scores are

• Malcolm Granville (Auckland Grammar School), 22
• Stephen Mackereth (King’s College), 16
• Yuan (Edward) Wang (Hillcrest High School), 15
• Tom Yan (Auckland Grammar School), 21
• Robert Zhang (Auckland Grammar School), 16
• Sicong Zhang (Auckland International College), 16

for a total of 106 points – about 6 or so points behind the United Kingdom, and 22 points behind Australia. The team each have a perfect score on at least one problem; three have perfect scores on two, and two have perfect scores on three. The Dutch team all have two perfect scores each, and a total of 94 points.

The postponement of problem two worked in our favour, as it gave us a chance to find an extra two points for Stephen that we hadn’t seen initially. And the second postponement went just as we’d expected, and we came away with the five sevens and one six the team deserved, after twenty minutes going through the remaining three scripts line by line. But we ended up having a third postponement, on problem four. A certain NZL1 had solved both geometry problems analytically, using complex numbers; and while both solutions were perfectly correct, and each only 3-4 pages long, they had each taken me several hours and eight pages of work to check. The one for problem four in particular had a step that involved equating a three by four term expansion with a six by six, cancelling terms and then factoring as six terms times four; so when the co-ordinators wanted to check the solution line by line, you can imagine it took some time…

I’d anticipated receiving solutions via complex geometry, so had come to Kazakhstan armed with two sheets of useful formulae, and had solved problem four myself using complex numbers (but a slightly different method) in Almaty. I’d also set up problem two (correctly, as it turned out!), but not had the stamina to carry it out. Moreover (and at great risk of being awarded the golden microphone, for the most speeches at the jury meetings!) I’d succeeded in getting a motion passed that “an incomplete analytic solution, that can be easily completed to a full solution” would receive three points instead of zero. All this preparation and my careful check of Malcolm’s script paid off. Ilya did most of the co-ordinating in Russian, with me writing the occasional equation or feeding Ilya some explanation as needed; and at last we all smiled, shook hands all round on our sixth seven for the problem, and went to dinner. These two solutions are by now infamous among the leaders and deputies we spend time with….but a perfect seven is a perfect seven!

We can certainly expect some medals this year; but just how many, and what type, won’t be known until the cutoffs are decided at the final jury meeting tomorrow evening. Speculation is rife!