1,3

A critical set in an n x n array is a set C of given entries,

such that there exists a unique extension of C to an n x n Latin

square and no proper subset of C has this property.

H. Hatami and E. S. Mahmoodian, A lower bound for the size of the largest critical sets in Latin squares

Sequence in context: A138659 A020590 A063437 this_sequence A049792 A062851 A071979

Adjacent sequences: A134358 A134359 A134360 this_sequence A134362 A134363 A134364

nonn,hard

Ralf Stephan, Jan 16 2008