The box parameter for words counts how often two letters w j and w k define a “box” such that all the letters w j+1; ..., w k−1 fall into that box. It is related to the visibility parameter and other parameters on words. Three models are considered: Words over a finite alphabet, permutations, and words with letters following a geometric distribution. A typical result is: The average box parameter for words over an M letter alphabet is asymptotically given by 2n − 2n H M/M, for fixed M and n → ∞.
@article{bwmeta1.element.doi-10_2478_s11533-013-0277-x, author = {Helmut Prodinger}, title = {The box parameter for words and permutations}, journal = {Open Mathematics}, volume = {12}, year = {2014}, pages = {167-174}, zbl = {1290.05006}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0277-x} }
Helmut Prodinger. The box parameter for words and permutations. Open Mathematics, Tome 12 (2014) pp. 167-174. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0277-x/
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