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 0 ⊆ ℚ

Proof

Step Hyp Ref Expression
1 nn0ssz 0 ⊆ ℤ
2 zssq ℤ ⊆ ℚ
3 1 2 sstri 0 ⊆ ℚ