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Metamath Proof Explorer

Theorem nn0cn

Description: A nonnegative integer is a complex number. (Contributed by NM, 9-May-2004)

Ref Expression
Assertion nn0cn 
|- ( A e. NN0 -> A e. CC )

Proof

Step Hyp Ref Expression
1 nn0sscn 
 |-  NN0 C_ CC
2 1 sseli 
 |-  ( A e. NN0 -> A e. CC )