Expression 4: "a" equals Start sum from "n" equals 1 to "k" , end sum, StartFraction, 1 Over "n" , EndFractiona=k∑n=11n
4
Expression 5: "b" equals Start sum from "n" equals 1 to "k" , end sum, StartFraction, floor left parenthesis, StartNestedFraction, "k" NestedOver "n" , EndNestedFraction , right parenthesis Over "k" , EndFractionb=k∑n=1floorknk