Number A Day

January 11, 2012 7:27 AM

NumberADay - Every working day, we post a number and offer a selection of that number’s properties.
posted by Wolfdog (30 comments total)

That's Numberwang!
posted by overeducated_alligator at 7:32 AM on January 11 [20 favorites]

It's hard to beat the compulsive semi-autism of a number theorist, unless you're into Gods and Earths-style Sacred Mathematics.
posted by joedanger at 7:42 AM on January 11

Wow. It takes all kinds to make an interesting world.
posted by Melismata at 7:47 AM on January 11

1 is the loneliest number.

2 can be as bad as 1. It's the loneliest number since the number 1.
posted by griphus at 7:49 AM on January 11 [5 favorites]

They've got so many of my favorite numbers there. Suddenly I don't feel so alone.
posted by Slack-a-gogo at 7:55 AM on January 11

And now I have Krafterwerk in my head!
posted by Slack-a-gogo at 7:57 AM on January 11

93 is a cake number. The nth cake number is the maximum number of pieces into which a (cylindrical) cake can be cut with n planar cuts. The first 10 cake numbers are 2, 4, 8, 15, 26, 42, 64, 93, 130, 176. There are 39 cake numbers below 10,000.

I'm going to need some very large cakes in order to verify the later terms in the sequence. Someone help me out with that?
posted by Wolfdog at 7:59 AM on January 11 [2 favorites]

For videos in a similar vein, check out numberphile.
posted by madcaptenor at 8:00 AM on January 11

I was hoping it would be the same content, but presented in a Sesame Street style:

Muppet 1: Today's number is . . . 1126! In the year 1126, Adelard of Bath translated Muhammad ibn-Musa al-Kwarizmi's arithmetic and astronomical tables into Latin.

Muppet 2: Adelard of Bath?? He must have been really clean!

Muppet 1 does facepalm. Sad trombone slide.
posted by Think_Long at 8:01 AM on January 11 [2 favorites]

I'm going to need some very large cakes in order to verify the later terms in the sequence. Someone help me out with that?

Heh, a favorite presentation at math camp was on the Cake Cutting Problem. Everybody liked it when groups would bring practical demonstrations.
posted by kmz at 8:07 AM on January 11

Like a lot of x Every Day blogs, they are going to run out of stuff to write about in like three months.
posted by gauche at 8:08 AM on January 11

Like a lot of x Every Day blogs, they are going to run out of stuff to write about in like three months.

Incorrect.

Theorem: Every positive integer is interesting.
Proof: Suppose there exists a non-interesting positive integer. By the well-ordering principle, there is a smallest such number. But by being the smallest non-interesting integer, it is interesting. Contradiction. Thus every positive integer is interesting, QED.
posted by kmz at 8:16 AM on January 11 [7 favorites]

Incorrect.

I was actually more going for the whole "what will they write about when they run out of numbers" angle.
posted by gauche at 8:18 AM on January 11

I'm decent enough at math but haven't been "the math guy" since about 7th grade. But I still like numbers in strange ways. There was a Mexican restaurant in my old neighborhood that, while decent enough, was not any better than the one that was right outside our back door. But I always insisted on ordering from them because their phone number, which was prominently displayed on their sign (which I walked under most workdays), was 784-1212, and not only is 12/12/74 my birthday but 7*12 is 84. And I thought all of that was really neat. And would tell the boring ass story to anyone new who was walking with me past the place.

(The seemingly-sudden mainstream appeal of "geek/nerd/dork cuteness" particularly in my gay guy generation was really brought to my attention when I realized dudes I liked were not only not put off by things like this, but found it appealing.)

Sites like this make me feel not only less alone but like I'm not doing it right. Thanks for this.
posted by MCMikeNamara at 8:20 AM on January 11 [1 favorite]

How...bizarre.
posted by SLC Mom at 8:21 AM on January 11

I have a pure maths degree and I'm afraid I found the cited facts about 1293 entirely un-interesting.
posted by mary8nne at 8:21 AM on January 11

I remember some sort of joke about a mathematician who said that every number was interesting. Someone else popped up with, OK, what about this number? And the mathematician responded that it was interesting because it was the lowest number that wasn't interesting.
posted by Chocolate Pickle at 8:28 AM on January 11 [2 favorites]

I hope there's a bit about 6 living in constant fear of 7...
posted by bxyldy at 8:28 AM on January 11 [1 favorite]

I remember some sort of joke about a mathematician who said that every number was interesting. Someone else popped up with, OK, what about this number? And the mathematician responded that it was interesting because it was the lowest number that wasn't interesting.

I wonder if you're conflating the jokey least uninteresting proof with an anecdote (told by Hardy) about the unbelievably genius Ramanujan?

I remember once going to see him when he was lying ill at Putney. I had ridden in taxi cab number 1729 and remarked that the number seemed to me rather a dull one, and that I hoped it was not an unfavorable omen. "No," he replied, "it is a very interesting number; it is the smallest number expressible as the sum of two cubes in two different ways."

posted by kmz at 8:34 AM on January 11

Previously
posted by Obscure Reference at 8:39 AM on January 11 [1 favorite]

992 arguments.
992, quit just a-fightin'.
992, I'm sick of you.
posted by shakespeherian at 9:06 AM on January 11

I for one, can't wait until they do the first non-interesting integer. What will they find to say about it?
posted by thelonius at 9:16 AM on January 11

Like a lot of x Every Day blogs, they are going to run out of stuff to write about in like three months.
This is true, if they limit themselves to positive integers, make the second post 1.5 months after the first, the third post after another 0.75 months, the fourth post after another 0.375 months, and so on.
posted by Wolfdog at 9:22 AM on January 11 [1 favorite]

I couldn't look at this without heading over to the New Aeon English Qabala for a little helping of the crazy.

Today's number - 1293 - is kind of a dead end, but 431 (1293 = 3 x 431) is a veritable treasure trove! For instance, 431 = "president of the united states," "UNION - WITH THE - KING OF KINGS and LORD of LORDS" and "WELL NOW - WHAT DO YOU THINK OF - THE MYSTICAL CROW"

What now, indeed?!?
posted by malocchio at 9:25 AM on January 11

Twelve....untha untha doo doo doo deew....
posted by Fizz at 9:44 AM on January 11

Feynman's memoirs are have a bunch of interesting number stories. The man had a gift for algebra. He also had an anecdote about 1729 to go along with Hardy's.

The great Futility Closet (run by a mefite I think?) is full of numerical oddities.
posted by no regrets, coyote at 9:53 AM on January 11

I have a pure maths degree and I'm afraid I found the cited facts about 1293 entirely un-interesting.

It's always been my impression that mathematicians find number theorists to be nerdy to an extent at least equal to that with which the general population finds mathematicians to be nerdy.
posted by invitapriore at 10:23 AM on January 11

the unbelievably genius Ramanujan

Seeing this post immediately made me think of the quip about every positive integer being one of Ramanujan's personal friends. In fact upon looking it up I find that the quip was made by another mathematician after hearing the taxicab anecdote.

If you want to take this to the next level (albeit with the same cardinality) check out The Online Encyclopedia of Integer Sequences (mefi mefi).
posted by hattifattener at 12:37 AM on January 12

73,492 is the smallest number containing the digits 7, 3, 4, 9, and 2 in that order.
posted by straight at 9:05 AM on January 12

As soon as I went to bed last night I realized that I got my cardinality joke backwards up there, obviously infinite integer sequences have cardinality at least as large as the reals, duh.
posted by hattifattener at 11:48 AM on January 12