The Penumbra primes
— June 2012, Oakland
I am up to something. These are my supplies:
Earlier this month, I sent a message out to my email list, and in part it laid out a little competition:
So here’s my scheme: I’d like to send five [galleys of Mr. Penumbra’s 24-Hour Bookstore] out to you… but then I’d like you to pass them on when you’re finished, and I’d like to try to keep track of them over the next four months. Who knows? Maybe they’ll end up somewhere interesting. Maybe they’ll end up with some interesting notes in the margins.
If you’d like to be one of my patient zeroes (patients zero?), just follow the link below and give me a prime number of your choosing. I’ll send books to the five people who choose the lowest unique prime numbers. So, if you pick 2 but seven other people pick 2, no book for you. If you pick 3 and no one else picks 3, you get a book.
Out of a few thousand email recipients, just about 500 people put a prime in the hat, and the distribution of picks was interesting. Here’s the total for each prime from 2 to 199 (or a shorter range if you’re reading this on a smaller screen):
It’s the classic long-tail distribution that characterizes so much behavior on the web and elsewhere, except it’s sort of nudged over to the right. That nudge is people thinking: Everyone else is going to pick the low primes… but not me! And of course everyone else is thinking exactly the same thing.
Beyond 199, there’s a very long, very sparse tail of higher picks. The very highest was 333,667—a sexy prime!
The person who picked the first winning prime, 109, told me:
I actually made a serious effort to choose a prime number which was high enough to be above the fray of 11s and 31s, lower than the four-digit crowd, and profoundly uninteresting as a number in its own right for maximum uniqueness probability.
Strategic number selection is totally in the spirit of this book.
So now five books are in the mail, winging their way to the strategists who uniquely chose primes 109, 131, 137, 167, and 173, in Vancouver, Los Angeles, the UK, Australia, and Seattle, respectively.
But these are more than mere galleys. They are the Penumbra primes, each with a blue-lined library card and a broad sticker bearing instructions to its recipient. These books come with a responsibility: keep them moving. My hope is that by the time Penumbra is released in October, they will have traveled a bit and picked up some notes in the margins—some dirt between the pages. If their recipients all play by the rules, we’ll be able to keep track of them, and in October we’ll make a map of their travels. Maybe other things will emerge, too: new rules I haven’t even imagined.
Godspeed, Penumbra primes! May you find your readers swiftly and may they receive you in high spirits. Summer is here, and there’s reading to be done.
P.S. There might, in fact, be more than five primes out there. There might, after all, have been special shipments to rogue recipients. You never know…
P.P.S. Want to participate in the next competition involving free books and/or prime numbers? Join my email list.
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