Bowline has a more symmetric triangular shaped knot. A slipped version of the Cossack knot is called Kalmyk loop. Bowline The bowline ( or ) is an ancient and simple knot used to form a fixed 'eye' at the end of a rope. It has the virtues of being both easy to tie and untie; most notably, it is easy to untie after being subjected to a load. The bowline is sometimes referred to as "King of the knots" because of its importance. It is one of the four basic maritime knots (the other three are figure-eight knot, reef knot and
Arf invariant of a knot if they are related by a finite sequence of pass-moves, which are illustrated below: (no figure right now) Every knot is pass-equivalent to either the unknot or the trefoil; these two knots are not pass-equivalent and additionally, the right- and left-handed trefoils are pass-equivalent. Now we can define the Arf invariant of a knot to be 0 if it is pass-equivalent to the unknot, or 1 if it is pass-equivalent to the trefoil. This definition is equivalent to the one above. Vaughan Jones showed that the Arf invariant can be obtained by taking the partition function of a signed planar