Metamath Proof Explorer


Theorem fz1ssnn

Description: A finite set of positive integers is a set of positive integers. (Contributed by Stefan O'Rear, 16-Oct-2014)

Ref Expression
Assertion fz1ssnn
|- ( 1 ... A ) C_ NN

Proof

Step Hyp Ref Expression
1 elfznn
 |-  ( a e. ( 1 ... A ) -> a e. NN )
2 1 ssriv
 |-  ( 1 ... A ) C_ NN