Difference between revisions of "Exponential integral Ei series"

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==References==
 
==References==
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[[Category:Theorem]]
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[[Category:Unproven]]

Revision as of 08:06, 8 June 2016

Theorem

The following formula holds for $x>0$: $$\mathrm{Ei}(x) = \gamma + \log x + \displaystyle\sum_{k=1}^{\infty} \dfrac{x^k}{kk!},$$ where $\mathrm{Ei}$ denotes the exponential integral Ei, $\log$ denotes the logarithm, and $\gamma$ denotes the Euler-Mascheroni constant.

Proof

References