Einstein function

In mathematics, the Einstein function, named after Albert Einstein, is a name occasionally used for one of these functions.

$$\frac{x^2{e}^x}{(e^x-1{)}^2}$$

$$\frac{x}{e^x-1}$$

$$\log (1-e^{-x})$$

$$\frac{x}{e^x-1}-\log (1-e^{-x})$$

References

• E W Lemmon, R Span, 2006, Short Fundamental Equations of State for 20 Industrial Fluids, J. Chem. Eng. Data 51 (3), 785–850 .
• Wolfram MathWorld: http://mathworld.wolfram.com/EinsteinFunctions.html