Checkered Doughnuts

toroidal magic square - from mathematical circles

Roll this magic square into a tube by joining the upper and lower edges, then join the ends of the tube. Every row, column, and diagonal on the resulting torus will add to 34.

toroidal chess problem, from petrovic, mathematics and chess

Bend this chessboard similarly into a torus, then mate in 4.

Hint: The solution comprises only two lines.

Click for Answer