A note on the completion of partial latin squares
نویسندگان
چکیده
The problem of completing partial latin squares to latin squares of the same order has been studied for many years. For instance, in 1960 Evans [9] conjectured that every partial latin square of order n containing at most n− 1 filled cells is completable to a latin square of order n. This conjecture was shown to be true by Lindner [12] and Smetaniuk [13]. Recently, Bryant and Rodger [6] established necessary and sufficient conditions for completing an arbitary 2 by n latin rectangle to an n by n symmetric latin square. Colbourn [8] demonstrated that the problem of determining whether an
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