Alex Bellos writes an occasional puzzle column for the Grauniad.
Yesterday he was asking for ways of inserting maths symbols into the list of numbers 10 9 8 7 ... 1 so as to make the expression evaluate to 2016. I quickly got an answer (10+9)*8*(7+6)+5*(4+3+2-1) but jules said I could only tweet it if I found three ways of doing it. A second solution is reached by noting that 10*9*(8+7+6) is 1890 and 6*(5*4+(3-2)*1) makes the remaining 126 to bring the total to 2016. Finally, 10*9*8*7*6/(5*(4-3)*(2+1)) works too.
I was writing the tweet and checking the numbers when I spotted that I'd used the 6 twice in the second solution. So that's how I found the
most elegant solution at the top. Sadly, the prize was for obscurantism instead.
Talking of winning, I've also won a climate bet! Chris Hope (of IPCC WG2 fame) owes me £666 in view of 2015 being not more than 0.1C colder than 2008. It may seem like a strange bet for him to take, since even in 2011 when the bet was placed, there seemed little prospect of such strong cooling. However, I gave him decent odds of 5:1 (ie I stood to lose £3333 if the improbable cooling had occurred). Of course Chris didn't really expect the world to cool so sharply, but he already had
established two bets the other way round (at evens with stakes of £1000) with Iam Plimer and Sir Alan Rudge, and was simply hedging his risk. In fact Chris was really taking the place of a bookmaker rather than gambler, and you can easily check that he was going to win a handy sum whatever the temperature did. I hope he manages to collect his winnings once the data are officially announced.
Of course the odds also look pretty good for my original $10,000 bet. I just checked (cos someone asked) that if this year is as warm as the one just past, then 2017 would have to be a full 1C colder for me to lose. There is certainly no year on record where such a dramatic year to year cooling has happened, even after a volcanic eruption, so perhaps we are in the realm of a large asteroid strike being required. Collecting, on the other hand, is a bit less clear-cut as I've not had any reply to the emails I have occasionally sent to my adversaries in recent years.
