An Etymological Dictionary of Astronomy and Astrophysics

The → base of the → natural logarithm.
It is defined as:

e = lim (1 + 1/n)ⁿ when n→ ∞. For n = 1, e = 2 and for n = 10, e = 2.5937424601, etc. The number e is → irrational (Euler, 1737) and → transcendental (Hermite, 1873).

See also: → number;