My definition of a magic rectangle:
Any $m \times n$ rectangle where $m \ne n$ and all the numbers $1, 2, 3,\dots, mn$ fit into the rectangle. All horizontal lines, vertical lines, and diagonal lines (albeit not the same length) add up to the same number called a "magic constant"
Do any magic rectangles exist? If so, what are some examples? Please include dimensions, magic constant, and if possible, the whole rectangle.
BONUS: How can you determine a rectangle's magic constant from its $m \times n$ dimensions?