Metamath Proof Explorer


Theorem nn0cni

Description: A nonnegative integer is a complex number. (Contributed by NM, 14-May-2003) Reduce dependencies on axioms. (Revised by Steven Nguyen, 8-Oct-2022)

Ref Expression
Hypothesis nn0rei.1 ⊢ A ∈ ℕ 0
Assertion nn0cni ⊢ A ∈ ℂ

Proof

Step Hyp Ref Expression
1 nn0rei.1 ⊢ A ∈ ℕ 0
2 nn0sscn ⊢ ℕ 0 ⊆ ℂ
3 2 1 sselii ⊢ A ∈ ℂ