Metamath Proof Explorer


Theorem press

Description: Predecessor is a subset of its successor. (Contributed by Peter Mazsa, 12-Jan-2026)

Ref Expression
Assertion press ( 𝑁 ∈ Suc → pre 𝑁𝑁 )

Proof

Step Hyp Ref Expression
1 sssucid pre 𝑁 ⊆ suc pre 𝑁
2 sucpre ( 𝑁 ∈ Suc → suc pre 𝑁 = 𝑁 )
3 1 2 sseqtrid ( 𝑁 ∈ Suc → pre 𝑁𝑁 )