Old Tricks
No. 009 · SATURDAY, 31 OCTOBER 2026 · SHAPES · ●●●●○

The sticker banner

A square pixel-art banner on a worktable, drawn on a grid of squares as a smiling robot. A girl stands beside it holding scissors, and a small printer and cutter sits on the right with stickers coming out.

Mai drew a 13 by 13 pixel-art banner for the coding club. The printer can only cut square stickers, and every sticker has to be a square of whole pixels.

Fewer stickers means less peeling for the club. The whole banner must be used, with no gaps and no overlaps, and one giant 13 by 13 sticker does not count.

What is the fewest square stickers the banner can be cut into? Prove it by cutting them.

Drag across the grid to cut a square. Tap a sticker to peel it off. Press Check when the banner is covered.