Expected Length of the Longest Common Subsequence for Large Alphabets
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چکیده
We consider the length L of the longest common subsequence of two randomly uniformly and independently chosen n character words over a k-ary alphabet. Subadditivity arguments yield that E [L] /n converges to a constant γk. We prove a conjecture of Sankoff and Mainville from the early 80’s claiming that γk √ k → 2 as k → ∞.
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تاریخ انتشار 2004