If you cut each shape from paper or card ... Some of the squares are filled in, can you see how to complete the pattern by colouring in 3 more squares? Play Guardians: Defenders of Mathematica ...

Infinitely many copies of a 13-sided shape can be arranged with no overlaps or gaps in a pattern that never repeats. David Smith, Joseph Samuel Myers, Craig S. Kaplan and Chaim Goodman-Strauss (CC ...