In mathematics, the Einstein function, named after Albert Einstein, is a name occasionally used for one of these functions.
x 2 e x ( e x − 1 ) 2 {\displaystyle {\frac {x^{2}e^{x}}{(e^{x}-1)^{2}}}}
x e x − 1 {\displaystyle {\frac {x}{e^{x}-1}}}
log ( 1 − e − x ) {\displaystyle \log(1-e^{-x})}
x e x − 1 − log ( 1 − e − x ) {\displaystyle {\frac {x}{e^{x}-1}}-\log(1-e^{-x})}
References Abramowitz, Milton; Stegun, Irene Ann, eds. (1983) [June 1964]. "Chapter 27". Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. Applied Mathematics Series. Vol. 55 (Ninth reprint with additional corrections of tenth original printing with corrections (December 1972); first ed.). Washington D.C.; New York: United States Department of Commerce, National Bureau of Standards; Dover Publications. p. 999. ISBN 978-0-486-61272-0. LCCN 64-60036. MR 0167642. LCCN 65-12253. E W Lemmon, R Span, 2006, Short Fundamental Equations of State for 20 Industrial Fluids, J. Chem. Eng. Data 51 (3), 785–850 doi:10.1021/je050186n. Wolfram MathWorld: http://mathworld.wolfram.com/EinsteinFunctions.html