Definition:Euler-Mascheroni Constant

Definition
The Euler-Mascheroni Constant $\gamma$ is the real number that is defined as:

where $H_n$ is the harmonic series and $\ln$ is the natural logarithm.

Also known as
This constant is otherwise known as Euler's Constant but must not be confused with Euler's number.

It was introduced by Euler in 1734.

Historical Note
In his 1790 work Adnotationes ad calculum integrale Euleri, Mascheroni published a calculation to 32 places of the value of this constant.

Only the first 19 places were accurate. The remaining ones were corrected in 1809 by Johann von Soldner.

One of the earliest apperarances of the symbol $\gamma$ was by Carl Anton Bretschneider in his 1837 paper.

Also see

 * Existence of Euler-Mascheroni Constant where its existence is demonstrated.