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Date: 25-7-2021
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Date: 26-6-2021
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If the knot is the boundary of a singular disk which has the property that each self-intersecting component is an arc for which consists of two arcs in , one of which is interior, then is said to be a ribbon knot.
Every ribbon knot is a slice knot, and it is conjectured that every slice knot is a ribbon knot.
Knot , illustrated above, is a ribbon knot (Rolfsen 1976, p. 225).
REFERENCES:
Rolfsen, D. Knots and Links. Wilmington, DE: Publish or Perish Press, p. 225, 1976.
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