hacker.org

laz0r wrote:Actually,
StringTake[ToString@Fibonacci[1500000], {1, -1, 20000}]
is more concise

Using Mathematica/Wolfram Alpha always looks like kind of cheating to me :p

Took approx. 199.827814006 s with Ruby. 8) def fibn(m) if m==0 out=0 else n=1 fibn=1 fibnMinus1=0 while n<m do n=n+1 h=fibn+fibnMinus1 fibnMinus1=fibn fibn=h end out=fibn end return out end def efind x k=fibn(x).to_s s="" for i in 0..k.length-1 if i%20000==0 then s+=k[i].to_s end end retur...

This challenge took my bot hours just to level up...
The boss summoned not until level 127. So i had to bot up to level 133...

But i really recommend Ruby for this challenge - mechanize and nokogiri are just nice.

Just a little algebra for this one.