Complete Diagonals of Latin Squares
Canadian mathematical bulletin, Tome 22 (1979) no. 4, pp. 477-481
Voir la notice de l'article provenant de la source Cambridge
J. Marica and J. Schönhein [4], using a theorem of M. Hall, Jr. [3], see below, proved that if any n − 1 arbitrarily chosen elements of the diagonal of an n × n array are prescribed, it is possible to complete the array to form an n × n latin square. This result answers affirmatively a special case of a conjecture of T. Evans [2], to the effect that an n × n incomplete latin square with at most n − 1 places occupied can be completed to an n × n latin square. When the complete diagonal is prescribed, it is easy to see that a counterexample is provided by the case that one letter appears n − 1 times on the diagonal and a second letter appears once. In the present paper, we prove that except in this case the completion to a full latin square is always possible. Completion to a symmetric latin square is also discussed.
Chang, Gerard J. Complete Diagonals of Latin Squares. Canadian mathematical bulletin, Tome 22 (1979) no. 4, pp. 477-481. doi: 10.4153/CMB-1979-062-3
@article{10_4153_CMB_1979_062_3,
author = {Chang, Gerard J.},
title = {Complete {Diagonals} of {Latin} {Squares}},
journal = {Canadian mathematical bulletin},
pages = {477--481},
year = {1979},
volume = {22},
number = {4},
doi = {10.4153/CMB-1979-062-3},
url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1979-062-3/}
}
Cité par Sources :