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POWhat's wrong with my Fibonacci sequence generator?
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copied!<p>I'm trying to solve <a href="http://projecteuler.net/problem=25" rel="nofollow">Problem #25 on Project Euler</a>. Here's what I've got so far:</p> <pre><code>def fibonacci(length): fibs = [0,1] while length > len(fibs): fibs.append(fibs[-1] + fibs[-2]) return fibs fibs = fibonacci(5000) for i in fibs: if len(str(i)) > 1000: print i ## The location of the number in the Fibonacci set. print [j for j, x in enumerate(fibs) if x == i] </code></pre> <p>Every number I've tested for (including some <a href="http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fibtable.html" rel="nofollow">large ones</a>) comes out with a match, but Project Euler isn't accepting the answer I'm getting.</p> <p>I read that the answer is the 4782th number, but I'm getting that the first number with over 1000 digits is the 4787th,</p> <pre><code>11867216745258291596767088485966669273798582100095758927648586619975930687764095025968215177396570693265703962438125699711941059562545194266075961811883693134762216371218311196004424123489176045121333888565534924242378605373120526670329845322631737678903926970677861161240351447136066048164999599442542656514905088616976279305745609791746515632977790194938965236778055329967326038544356209745856855159058933476416258769264398373862584107011986781891656652294354303384242672408623790331963965457196174228574314820977014549061641307451101774166736940218594168337251710513138183086237827524393177246011800953414994670315197696419455768988692973700193372678236023166645886460311356376355559165284374295661676047742503016358708348137445254264644759334748027290043966390891843744407845769620260120918661264249498568399416752809338209739872047617689422485537053988895817801983866648336679027270843804302586168051835624516823216354234081479331553304809262608491851078404280454207286577699580222132259241827433 </code></pre> <p>and Project Euler is saying every answer I've tried is wrong. (Obviously I didn't try 4782 yet, as that would be cheating.)</p> <p>I'm tantalizingly close, and clearly something is going wrong, but what?</p>

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