 Consider a hyperelliptic curve formula_249 of genus formula_5 over a field formula_2.A divisor formula_116 of formula_70 is called reduced if it has the form formula_254 where formula_255, formula_256 for all formula_257 and formula_258 for formula_259.Note that a reduced divisor always has degree 0, also it is possible that formula_260 if formula_259, but only if formula_262 is not a Weierstrass point.