On the spectrum of r-orthogonal Latin squares of different orders

‎Two Latin squares of order n n are orthogonal if in their superposition‎, ‎each of the n 2 n2 ordered pairs of symbols occurs exactly once‎. ‎Colbourn‎, ‎Zhang and Zhu‎, ‎in a series of papers‎, ‎determined the integers r r for which there exist a pair of Latin squares of order n n having exactly...

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Bibliographic Details
Main Authors: Hanieh Amjadi, Nasrin Soltankhah, Naji Shajarisales, Mehrdad Tahvilian
Format: Article
Language:English
Published: University of Isfahan 2016-06-01
Series:Transactions on Combinatorics
Subjects:
Online Access:http://www.combinatorics.ir/article_11665_93148cb85b3fdaf4b4abfe8412331040.pdf
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Summary:‎Two Latin squares of order n n are orthogonal if in their superposition‎, ‎each of the n 2 n2 ordered pairs of symbols occurs exactly once‎. ‎Colbourn‎, ‎Zhang and Zhu‎, ‎in a series of papers‎, ‎determined the integers r r for which there exist a pair of Latin squares of order n n having exactly r r different ordered pairs in their superposition‎. ‎Dukes and Howell defined the same problem for Latin squares of different orders n n and n+k n+k‎. ‎They obtained a non-trivial lower bound for r r and solved the problem for k≥2n3 k≥2n/3‎. ‎Here for k<2n3 k<2n/3‎, ‎some constructions are shown to realize many values of r r and for small cases (3≤n≤6) (3≤n≤6)‎, ‎the problem has been solved‎.
ISSN:2251-8657
2251-8665