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On a Speculated Relation Between Chvátal–Sankoff Constants of Several Sequences

Published online by Cambridge University Press:  01 July 2009

M. KIWI  and
J. SOTO
M. KIWI
Affiliation:
Departamento de Ingeniería Matemática, Centro de Modelamiento Matemático (UMI 2807, CNRS), University of Chile (e-mail: [email protected])
J. SOTO
Affiliation:
Department of Mathematics, MIT, Cambridge, MA 02139, USA (e-mail: [email protected])
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Abstract

It is well known that, when normalized by n, the expected length of a longest common subsequence of d sequences of length n over an alphabet of size σ converges to a constant γσ,d. We disprove a speculation by Steele regarding a possible relation between γ2,d and γ2,2. In order to do that we also obtain some new lower bounds for γσ,d, when both σ and d are small integers.

Type
Paper
Information
Combinatorics, Probability and Computing , Volume 18 , Issue 4 , July 2009 , pp. 517 - 532
Copyright
Copyright © Cambridge University Press 2009

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