# Accordion is width-200

The correlated neighbour on a plane is the **next row**. Pairs `(2i, 2i+1)`.

Mirror pairs `i` with `H-1-i`. Translate pairs `i` with `i+H/2`. Both are distant. On a screenshot that stacks browser chrome on the taskbar. Owner named that bug.

Width-200 is the same law: one `<BQQQ>` gate per scanline. Next row = next gate. `ground/WIDTH200.md`.

The fold itself moves no information. Packed size at true bit width stays flat. Whole-byte padding made depth 3 look special — that was 4× bloat at fold 1, not geometry.

Door: `accordion.html` · `foldbook.html`. CLI: `foldpack.py --mode adjacent`.