The generalized integro-exponential function. (English) Zbl 0593.33001
This paper summarizes analytic results and gives rational minimax approximations useful in computing van de Hulst’s ”generalized integro- exponential function”
\[
E^ j_ s(z)=[(-1)^ j/j!]\partial^ jE_ s(z)/\partial s^ j,
\]
where \(E_ s(z)\) is the exponential integral.
Reviewer: E.Kreyszig
Digital Library of Mathematical Functions:
𝑝-Derivatives ‣ §8.19(v) Recurrence Relation and Derivatives ‣ §8.19 Generalized Exponential Integral ‣ Related Functions ‣ Chapter 8 Incomplete Gamma and Related Functions§8.19(xi) Further Generalizations ‣ §8.19 Generalized Exponential Integral ‣ Related Functions ‣ Chapter 8 Incomplete Gamma and Related Functions