Definition df-pli 7113

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 × N))

Detailed syntax breakdown of Definition df-pli

Step	Hyp	Ref	Expression
1		cpli 7081	. 2 class +N
2		coa 6310	. . 3 class +o
3		cnpi 7080	. . . 4 class N
4	3, 3	cxp 4537	. . 3 class (N × N)
5	2, 4	cres 4541	. 2 class ( +o ↾ (N × N))
6	1, 5	wceq 1331	1 wff +N = ( +o ↾ (N × N))

This definition is referenced by:  addpiord  7124  dmaddpi  7133