## Golden Days

I haven’t been able to avoid people on my Twitter feed pointing out today’s a Pythagorean Triple, if you write out the month and day as digits and only use the last two digits of the year. There aren’t many such days; if I haven’t missed one there’s only fourteen per century, and we’ve just burned through the tenth of them. But if you want to have a little fun you might try working out whether I’m correct, and when the next one is going to be.

I don’t know of an efficient way of doing this, the sort of thing where you set up a couple of equations and let your favorite version of Mathematica grind away a bit and spit out an array of dates. This seems like the sort of problem best done by working out sets of integers a, b, and c, where $a^2 + b^2 = c^2$, and figure out what sets of those numbers can plausibly even be arranged as dates.

The more mysterious thing to me is that I don’t remember this being so much pointed out when we had the same Pythagorean Triple day in May, and not at all when we were really rich with them back nearly a decade ago. But I wasn’t on Twitter back then; maybe that’s the problem. I also haven’t seen people complaining that it’s a trivial thing not worth pointing out; it may be trivial, but if we aren’t going to enjoy pretty alignments of numbers, what are we supposed to do?