Definition df-e 11612

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 11606	. 2 class _e
2		c1 7775	. . 3 class 1
3		ce 11605	. . 3 class exp
4	2, 3	cfv 5198	. 2 class ( exp ` 1 )
5	1, 4	wceq 1348	1 wff _e = ( exp ` 1 )

This definition is referenced by:  esum  11625  ere  11633  ege2le3  11634  efzval  11646  reeff1oleme  13487  loge  13582  logdivlti  13596