Definition df-ni 5000

Description: Define the class of positive integers. This is a "temporary" set used in the construction of complex numbers df-c 5240, and is intended to be used only by the construction.

Assertion

Ref	Expression
df-ni	|- N. = (om \ {(/)})

Detailed syntax breakdown of Definition df-ni

Step	Hyp	Ref	Expression
1		cnpi 4972	. 2 class N.
2		com 3131	. . 3 class om
3		c0 2280	. . . 4 class (/)
4	3	csn 2409	. . 3 class {(/)}
5	2, 4	cdif 2044	. 2 class (om \ {(/)})
6	1, 5	wceq 956	1 wff N. = (om \ {(/)})

This definition is referenced by:  elni 5004  pinn 5006  niex 5009  dmaddpi 5018  dmmulpi 5019

Copyright terms: Public domain