Mathematical Humor: Halloween vs Christmas Riddle

✨Mathplayground✨ (@mathplayground1)’s videos with original sound - ✨Mathplayground✨

What's the least number of blue squares one needs in a 4x4 grid of red and blue squares so that there is no loop of vertical and horizontal step that is all red or all blue? (For 2x2, one; for 3x3, two.) The least number for a 5x5 grid? #popular #math #viral #mathplayground