The span of an unoriented link diagram (also called the link spread) is the difference between the highest and lowest degrees of its bracket polynomial. The span is a topological invariant of a knot. If a knot has a reduced alternating projection of crossings, then the span of is .

# Link Span

## See also

Link## Explore with Wolfram|Alpha

## Cite this as:

Weisstein, Eric W. "Link Span." From *MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/LinkSpan.html