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Metamath Proof Explorer

Theorem nn0ssq

Description: The nonnegative integers are a subset of the rationals. (Contributed by NM, 31-Jul-2004)

Ref Expression
Assertion nn0ssq ℕ0 ⊆ ℚ

Proof

Step Hyp Ref Expression
1 nn0ssz ⊢ ℕ0 ⊆ ℤ
2 zssq ⊢ ℤ ⊆ ℚ
3 1 2 sstri ⊢ ℕ0 ⊆ ℚ