OFFSET
1,2
COMMENTS
A027433(n)/4^n gives the expected value of the length of a longest common subsequence between two random binary strings of the length n, and a(n)/(4^(n-1)*(4^n - 1)) gives the variance (the squared standard deviation) of that length.
LINKS
Vacláv Chvátal, David Sankoff, Longest Common Subsequences of Two Random Sequences, Journal of Applied Probability, Vol. 12, No. 2 (Jun., 1975), pp. 306-315, DOI: 10.2307/3212444.
Wikipedia, Chvátal-Sankoff constants.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Vladimir Reshetnikov, May 13 2016
STATUS
approved