Chebyshev expansions for Abramowitz functions

Abstract The paper discusses the evaluation of the functions J n (x) =∫0∞t n exp(−t 2 −x⧸t)dt by using Chebyshev expansions. It is known that values of J n can be derived by a recurrence based on J 0 , J 1 and J 2 so only these functions are considered. Coefficients are derived which are accurate to 20 decimal places.