Metamath Proof Explorer


Theorem n0sex

Description: The set of all non-negative surreal integers exists. (Contributed by Scott Fenton, 17-Mar-2025)

Ref Expression
Assertion n0sex
|- NN0_s e. _V

Proof

Step Hyp Ref Expression
1 df-n0s
 |-  NN0_s = ( rec ( ( x e. _V |-> ( x +s 1s ) ) , 0s ) " _om )
2 1 a1i
 |-  ( T. -> NN0_s = ( rec ( ( x e. _V |-> ( x +s 1s ) ) , 0s ) " _om ) )
3 2 noseqex
 |-  ( T. -> NN0_s e. _V )
4 3 mptru
 |-  NN0_s e. _V