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SOLO-023 · Nonogram

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The Fragmented Grid

Black out the boxes of this 16 × 16 grid to satisfy all series.

Materials: Pencil and gum; grid below.

Rules you need

The puzzle

The series and possible pre-filled boxes are the only data of the problem. ■ = already black box, · = already proven empty box; the white boxes without symbol remain unknown. No symmetry or recognizable image should be assumed.

Coordinates: lines from top to bottom, columns from left to right.
L / CC111112C211111111C321111C411C522211C611121C72112C8121C911222C1011131C11162C12173C1321131C141116C1542131C164111
L11 · 1 · 2
L21 · 2 · 2 · 1 · 1 · 1
L32 · 1 · 2
L41 · 1 · 2 · 2 · 2·
L52 · 1 · 1 · 1 · 2
L61 · 1 · 3 · 1
L73 · 2 · 3 · 3
L82 · 2 · 1
L91 · 3 · 1 · 4
L101 · 1 · 3 · 1 · 2■
L111 · 1 · 1 · 2
L121 · 1 · 3 · 2
L131 · 2 · 2 · 1 · 3·
L141 · 1 · 1 · 1 · 1 · 2
L151 · 2 · 2 · 1 · 1
L163 · 1 · 3 · 3
Why this level?

The simple intersection blocks; the crosses require an analysis of nested cases (depth 7, 34 branches impossible in the solver). Editorial level based on this need for coordination, not on the only format of the grid.

Your workspace

Write down your assumptions separately from deductions you have proved.