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Numbers API - An API for interesting facts about numbers (numbersapi.com)
74 points by divad12 5216 days ago
10 comments

http://numbersapi.com/1729/math "1729 is a plain old number."

Can't recognize Hardy-Ramanujan number?

Also the smallest perfect number: http://numbersapi.com/6/math "6 is the smallest number of distinct isosceles right triangles that will tile an isosceles right triangle."

Ha, good catch. http://numbersapi.com/1729 (the trivia version) gives the Ramanujan fact, while we have multiple math facts for 6 (refresh a few times to get "smallest perfect number").

We're still working to build our database of facts. Feel free to send suggestions to numbersapi at google mail, and we may add a feature for user-submitted facts.

See http://numbersapi.com/1729:

> 1729 is the smallest number representable in two different ways as a sum of two positive cubes, as Ramanujan stated on the spot.

It looks like they've fixed the one for 1729.
perhaps it is a pun on Hardy, who thought it was an uninteresting number?
Hi, I'm the co-creator of this service. Blog post with more info: http://david-hu.com/2012/03/05/announcing-numbers-api.html

We welcome any feedback and are willing to answer any questions. Thanks!

Minor bug with your ticker and negative numbers: http://cl.ly/3S1x1H3t1t1D22122A0z
Thanks for pointing that out. The ticker came from some work I did while interning at Khan Academy, and was not originally meant for negative numbers. If I get some time, I may make it into a jQuery plugin and make it work for more cases and be configurable.
Is there a way to suggest entries?
Not right now, but we're looking to possibly add this feature. For now, feel free to send any suggestions to numbersapi at google mail.
There is now: click the "+ Add a trivia fact..." on http://numbersapi.com/
We will finally be able to answer humanity's most pressing question: what is the smallest uninteresting positive integer?
what is the smallest uninteresting positive integer?

Doesn't discovering that unique number instantly make it interesting? :)

It's an API, so I have this code running now:

    for i in xrange(10000):
        print i
        trivia = requests.get('http://numbersapi.com/%d' % i).text
        math = requests.get('http://numbersapi.com/%d/math' % i).text
        if 'boring' in math and ('plain' in trivia or 'boring' in trivia):
            print math, trivia    
            break
        time.sleep(2)
http://numbersapi.com/1321/trivia has given me both "1321 is a most unremarkable number" and "1321 is an uninteresting number", to give an upper bound. ;-)
223.

EDIT: 219 is definitely smaller than 223.

219

Edit: on the other hand, in the math category "219 is the smallest number that can be represented as a sum of four positive cubes in two different ways."

223 is a US date-prime. 2 and 23 is prime, and so is 223.

That may be a stretch, but it qualifies as something interesting.

I hope you know the answer to this?
You can get a lot of number facts using Wolfram|Alpha and its API

http://www.wolframalpha.com/input/?i=1729

Wolfram Alpha is great for mathematical properties of numbers, while we have trivia facts and are looking to gather more (eg. from world records, numbers in nature, statistics, almanacs, news).
Similar - The On-Line Encyclopedia of Integer Sequences: https://oeis.org/
Don't forget a crossdomain.xml file!
Oops, terrible oversight. Fixed now - http://numbersapi.com/#1337 :)

Feel free to send entry suggestions to numbersapi at google mail. We may add a feature for this soon.

420, 666, and 777
Why?