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((8^(5/4))^(((2/(0-(7+1)))^9)^(3-6))) = 2.718281848685499 ~ e +/- 2.0226453845140213e-08

That was fun. Although I'm having trouble confirming the answer... - Also I'm meant to be packing.

http://play.golang.org/p/G_Y5SblSuv for some brute force eval :)

Edit: This could be a nice demonstration for a genetic algorithm: A clearly defined fitness function yet an unknown (unknowable?) goal, and a distinct representation of the genes. I'm not sure how hereditary the fitness is though.

Further edit: Just 4 digits: (6-(8^(4/7))) 2.718658575969448 0.00037674751040306376 - I hope this is a) correct, b) interesting to someone else.



You beat me by about 5 orders of magnitude, but it is possible to do better, by another 200000 orders of magnitude or so! :-)

Best I've seen is given in this discussion: http://www.reddit.com/r/math/comments/zakqh/using_the_number...


Oh well, I'm sure it would have got there eventually...

Interesting problem nonetheless.


I have one of those, a symbolic regressor (not genetic) lying around in a broken state. The last working version gave:

  short: 2981^ (1/8)
  less short: (2574 + 4903 ^ (1/4))/950
I used: http://apod.nasa.gov/htmltest/gifcity/e.1mil

Perhaps I am misunderstanding your output but it is only correct up on till: 2.7182818


Digit concatenation was not allowed in the original challenge. If digit concatenation is allowed, then I believe that the best known is:

   (1+9^(-4^(7x6))^(3^(2^85))
which gives e to 18457734525360901453873570 decimal digits.


"Digits may not be concatenated--for instance, you cannot get a 23 by simply placing the 2 next to the 3."

I think that renders both of your solutions invalid, but cool nonetheless!


Oh sorry guys missed the digit concatenation bit. In that case I get:

  (9 - (5/7)^(1/2)) / 3 
I was tired when I saw that post, it was late/early. rmccue, I also seemed to have missed that you gave an error bound =(




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