Corner in an integer grid
= Corner in an integer grid
{title2=$\{(x,y),(x,y+d),(x+d,y)\},\quad d\ne0$}
= Corners in an integer grid
{synonym}
A corner consists of these three points in the <integer> grid, all contained in the set being studied. The displacement may be positive or negative, but must be nonzero, so the points are distinct. The <corners theorem> guarantees a corner in every subset of positive fixed <density of a finite subset> of a sufficiently large square grid.