Definition df-pli 7372

Description: Define addition on positive integers. This is a "temporary" set used in the construction of complex numbers, and is intended to be used only by the construction. (Contributed by NM, 26-Aug-1995.)

Assertion

Ref	Expression
df-pli	|- +N = ( +o |` ( N. X. N. ) )

Detailed syntax breakdown of Definition df-pli

Step	Hyp	Ref	Expression
1		cpli 7340	. 2 class +N
2		coa 6471	. . 3 class +o
3		cnpi 7339	. . . 4 class N.
4	3, 3	cxp 4661	. . 3 class ( N. X. N. )
5	2, 4	cres 4665	. 2 class ( +o |` ( N. X. N. ) )
6	1, 5	wceq 1364	1 wff +N = ( +o |` ( N. X. N. ) )

This definition is referenced by:  addpiord  7383  dmaddpi  7392