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Configuration #55

RSST-R-0055-COMP-1976discharging rule R6

ring size 6

vertices 10 · edges 18

Free completion

edge 0–1edge 0–5edge 0–6edge 0–9edge 1–2edge 1–8edge 1–9edge 2–3edge 2–7edge 2–8edge 3–4edge 3–7edge 4–5edge 5–6edge 5–9edge 6–7edge 7–8edge 7–9vertex 0 · deg 4 · B·ochre · ringvertex 1 · deg 4 · A·vermilion · ringvertex 2 · deg 4 · B·ochre · ringvertex 3 · deg 3 · C·viridian · ringvertex 4 · deg 2 · B·ochre · ringvertex 5 · deg 4 · A·vermilion · ringvertex 6 · deg 3 · C·viridianvertex 7 · deg 5 · A·vermilionvertex 8 · deg 3 · C·viridianvertex 9 · deg 4 · C·viridian
100%

Outer cycle (bold ring) is the configuration's boundary; interior vertices form the reducible piece. A configuration is D-reducible when every 4-coloring of its ring either extends to the interior or can be Kempe-modified into one that does.