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Old 07-24-2005, 11:40 PM
jason_t jason_t is offline
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Join Date: Nov 2004
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Default Re: if you get this you are smart

This one is easy.

answer: <font color="white">1610 27370 1211</font>

The sequence is a mixture of Conway's look and say sequence and multiplying by the nth prime.

The look and say sequence is incredibly famous. I first encounterd it in a freshman computer science course on computer architecture. I never paid attention to lecture and was always trading notes with a friend. He passed me the first five terms of the sequence and told me to find the next. I found it and was quite pleased with myself and became rather obsessed with the sequence. One interesting thing that can be asked about the sequence is how much longer is the nth term than the (n-1)th term? I was never able to answer this question but it turns out that Conway asked this question too and found the answer. In fact, he showed for any look and say sequence (that is, you don't necessarily have to start with the number 1, you could start with any number you like and then do look and say on it) the length of the nth term is approximately C = 1.303577269034296... the length of the (n-1)th term. That number C is the only positive root of a certain degree 71 polynomial.
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