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Re: Conjecture about permutations
Posted:
Jun 8, 2013 12:38 PM


On Sat, 08 Jun 2013 08:49:15 0700, Vincent Granville wrote:
> An interesting conjecture about permutations is made in this article. Can you prove it? There's a reward for doing so. > > URL: http://www.analyticbridge.com/profiles/blogs/correlationandrsquaredforbigdata
Is the conjecture you refer to the one about whether q(n) = O(n)^{c+1}, stated in the paragraph that begins "I conjecture that..." ? Or is it some other question?
On another topic: At the end of 2.2 you give an "Algorithm to generate a random permutation (p(0), p(1), ... , p(n1))" and ask, "what is the computational complexity of this algorithm?". It is Theta(n log n), as noted in <http://en.wikipedia.org/wiki/Coupon_collector%27s_problem>.
For a better randompermutation algorithm with Theta(n) performance, use Fisher?Yates shuffle. <http://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle>
 jiw



