Question 48
a) Is it possible for some $n$ to arrange 100 pawns in the cells of an $n \times n$ table so that at most one pawn stands in each cell and exactly 2 pawns stand in each $2 \times 2$ square?
b) Is it possible to arrange 110 pawns in the same way?
b) Is it possible to arrange 110 pawns in the same way?