We introduce the notion of premature partial Latin squares; these cannot be completed, but if any of the entries is deleted, a completion is possible. We study their spectrum, i.e., the set of integers \(t\) such that there exists a premature partial Latin square of order \(n\) with exactly \(t\) nonempty cells.
Citation
Ljiljana Brankovic, Mirka Miller, Peter Horak, Alexander Rosa. Premature Partial Latin Squares[J], Ars Combinatoria, Volume 063. 175-184. .