Metamath Proof Explorer


Definition df-mi

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

Ref Expression
Assertion df-mi 𝑵 = 𝑜 𝑵 × 𝑵

Detailed syntax breakdown

Step Hyp Ref Expression
0 cmi class 𝑵
1 comu class 𝑜
2 cnpi class 𝑵
3 2 2 cxp class 𝑵 × 𝑵
4 1 3 cres class 𝑜 𝑵 × 𝑵
5 0 4 wceq wff 𝑵 = 𝑜 𝑵 × 𝑵