Metamath Proof Explorer


Theorem 1arymaptf1o

Description: The mapping of unary (endo)functions is a one-to-one function onto the set of endofunctions. (Contributed by AV, 19-May-2024)

Ref Expression
Hypothesis 1arymaptfv.h H = h 1 -aryF X x X h 0 x
Assertion 1arymaptf1o X V H : 1 -aryF X 1-1 onto X X

Proof

Step Hyp Ref Expression
1 1arymaptfv.h H = h 1 -aryF X x X h 0 x
2 1 1arymaptf1 X V H : 1 -aryF X 1-1 X X
3 1 1arymaptfo X V H : 1 -aryF X onto X X
4 df-f1o H : 1 -aryF X 1-1 onto X X H : 1 -aryF X 1-1 X X H : 1 -aryF X onto X X
5 2 3 4 sylanbrc X V H : 1 -aryF X 1-1 onto X X