E

E or e may refer to:
* Extensible-E System (ExE), a system of notations by Sbiis Saibian
** Hyper-E notation (E#), a notation by Sbiis Saibian with growth rate \(f_\omega(n)\)
*** Extended Hyper-E Notation (xE#), a notation in ExE with growth rate \(f_{\omega^\omega}(n)\)
** Cascading-E notation (E^), a notation in ExE with growth rate \(f_{\varepsilon_0}(n)\)
*** Limited Extension Cascading-E Notation (LECEN), a notation in ExE with growth rate \(f_{\varepsilon_\omega}(n)\)
** Extended Cascading-E Notation (xE^), a notation in ExE with growth rate \(f_{\varphi(\omega,0,0)}(n)\)
*** Hyper-Extended Cascading-E Notation, a notation in ExE with growth rate \(f_{\varphi(1,0,0,0)}(n)\)
*** Nested Cascading-E notation
***
**Collapsing-E Notation (&E) a function with growth rate of \(\approx\) \(f_{\psi_0(\varepsilon_{\Omega+1})}(n)\) (the creator's expectation of this notation's limit, with respect to Buchholz's function)
***Extended Collapsing-E notation
**Expand-E notation
*Exploding Tree Function E(n), a googological function with growth rate \(f_{\omega+1}(n)\)
*A shorthand for scientific notation. For example, Avogadro's number can be approximated as 6.02E23, 6.02e23, 6.02E+23, or 6.02e+23.
*The symbol for the SI prefix exa-
*, equal to about 2.718281828.
==See also==
*Ε (Capital letter of ε)
*:Category:E-related numbers
Category:Numbers