Metamath Proof Explorer


Theorem xnn0nnd

Description: Conditions for an extended nonnegative integer to be a positive integer. (Contributed by Thierry Arnoux, 26-Oct-2025)

Ref Expression
Hypotheses xnn0nnd.1
|- ( ph -> N e. NN0* )
xnn0nnd.2
|- ( ph -> N e. RR )
xnn0nnd.3
|- ( ph -> 0 < N )
Assertion xnn0nnd
|- ( ph -> N e. NN )

Proof

Step Hyp Ref Expression
1 xnn0nnd.1
 |-  ( ph -> N e. NN0* )
2 xnn0nnd.2
 |-  ( ph -> N e. RR )
3 xnn0nnd.3
 |-  ( ph -> 0 < N )
4 1 2 xnn0nn0d
 |-  ( ph -> N e. NN0 )
5 elnnnn0b
 |-  ( N e. NN <-> ( N e. NN0 /\ 0 < N ) )
6 4 3 5 sylanbrc
 |-  ( ph -> N e. NN )