Hostname: page-component-77c89778f8-vpsfw Total loading time: 0 Render date: 2024-07-22T01:40:59.205Z Has data issue: false hasContentIssue false

An Approximation connected with e-x

Published online by Cambridge University Press:  20 January 2009

E. T. Copson
Affiliation:
St Andrews University.
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

One of the many interesting problems discussed by Ramanujan is concerned with the effect of truncating at its maximum term nn/n! the exponential series for en, where n is a positive integer. When n is large, the sum of the first n terms is, roughly speaking, half the sum of the whole series.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1933

References

page 201 note 1 Collected Papers of Srinivasa Ramanujan (1927), xxvi.Google Scholar

page 201 note 2 Journal London Math. Soc., 3 (1928), 225232.Google Scholar

page 201 note 3 Proc. London Math. Soc., (2), 29 (1928), 293308.Google Scholar

page 203 note 1 Bromwich, Infinite Series (1926), 485.Google Scholar

page 203 note 2 cfWatson, loc. cit.Google Scholar

page 204 note 1 Proc. London Math. Soc. (2), 17 (1918), 133. It also occurs in his treatise on Bessel Functions (1922), 236.Google Scholar