Cowboy bowline so easily pushed back by accident. However, there is no documentation to confirm this claim, and some Dutch knot tyers outright deny it. Another piece of unverified lore is that it is called a winter bowline because the exposed working end on the outside would blow in the wind and prevent it from freezing to the loop on ships in the north Atlantic during winter. (This suggests that the standard bowline would be the summer bowline.) "The Ashley Book of Knots" states that it is "distinctly inferior" to the standard bowline because of its similarity to the left-hand sheet bend.
Arf invariant of a knot the knot, constructed from a set of curves on a Seifert surface of genus "g" which represent a basis for the first homology of the surface. This means that "V" is a 2"g" × 2"g" matrix with the property that "V" − "V" is a symplectic matrix. The "Arf invariant" of the knot is the residue of Specifically, if formula_3, is a symplectic basis for the intersection form on the Seifert surface, then where formula_5 denotes the positive pushoff of "a". This approach to the Arf invariant is due to Louis Kauffman. We define two knots to be pass equivalent