Definition df-e 11831

Description: Define Euler's constant _e = 2.71828.... (Contributed by NM, 14-Mar-2005.)

Assertion

Ref	Expression
df-e	|- _e = ( exp ` 1 )

Detailed syntax breakdown of Definition df-e

Step	Hyp	Ref	Expression
1		ceu 11825	. 2 class _e
2		c1 7897	. . 3 class 1
3		ce 11824	. . 3 class exp
4	2, 3	cfv 5259	. 2 class ( exp ` 1 )
5	1, 4	wceq 1364	1 wff _e = ( exp ` 1 )

This definition is referenced by:  esum  11844  ere  11852  ege2le3  11853  efzval  11865  reeff1oleme  15092  loge  15187  logdivlti  15201