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 (unknown function "\overcrossing"): {\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.