Triple bowline larger than the two equal-sized loops. The size of the third loop depends on the length of the bight pulled through the loop. A bowline on the bight is a similar knot to the triple bowline. Instead of wrapping the bight around the standing end and then passing it back through the nipping loop, the two loops are passed through the bight so that it tightens on the standing end. It has only two active or available loops. This is used in rescue situations, especially in a case where there might be an injured person or people, as it forms
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