Notes for AKT-090910-2/0:15:44

Definitions of positive and negative crossings and the writhe of an oriented knot diagram.

Positive crossing: Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \,\overcrossing\,}

Negative crossing: Failed to parse (unknown function "\undercrossing"): {\displaystyle \,\undercrossing\,}

The writhe of an oriented knot diagram is the sum of the signs of all the crossings in the diagram.