Database
SURREAL NUMBERS
Conway cut representation
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leftno
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rightno
Metamath Proof Explorer
Ascii
Structured
Theorem
leftno
Description:
An element of a left set is a surreal.
(Contributed by
Scott Fenton
, 27-Feb-2026)
Ref
Expression
Assertion
leftno
⊢
(
𝐴
∈ ( L ‘
𝐵
) →
𝐴
∈
No
)
Proof
Step
Hyp
Ref
Expression
1
leftssno
⊢
( L ‘
𝐵
) ⊆
No
2
1
sseli
⊢
(
𝐴
∈ ( L ‘
𝐵
) →
𝐴
∈
No
)