A differential equation with six coefficients that sum to one is named for either Papperitz or this mathematician and generalizes the hypergeometric differential equation. This mathematician is the alphabetically latter namesake of the result that the Fourier transform of an L-one function vanishes at infinity. By introducing finer control of mesh size, Thomas Stieltjes improved an operation named for this mathematician (15[1])that is equivalent (-5[1])to the (-5[1])Darboux definition, (-5[1])which replaces (15[1])a requirement of the convergence of all tagged partitions with (*) upper and lower sums. This mathematician co-names a lemma with Henri Lebesgue, who also generalized an object named for this mathematician that might be approximated with (10[1])the midpoint or trapezoid rules. (10[1])For 10 points, (10[2])name this German mathematician whose namesake “sums” (10[1])are used to define (10[1])an integral. ■END■ (10[1])