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Date: 16-7-2021
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Date: 11-8-2021
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Date: 26-9-2016
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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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دراسة: عدم ترتيب الغرفة قد يدل على مشاكل نفسية
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علماء: تغير المناخ تسبب في ارتفاع الحرارة خلال موسم الحج
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العتبة العباسية تطلق المؤتمر العلمي لأسبوع الإمامة باللغة الإنجليزية
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