Database
REAL AND COMPLEX NUMBERS
Reflexive and transitive closures of relations
Reflexive-transitive closure as an indexed union
df-rtrclrec
Metamath Proof Explorer
Description: The reflexive, transitive closure of a relation constructed as the union
of all finite exponentiations. (Contributed by Drahflow , 12-Nov-2015)
Ref
Expression
Assertion
df-rtrclrec
⊢ t*rec = ( 𝑟 ∈ V ↦ ∪ 𝑛 ∈ ℕ0 ( 𝑟 ↑𝑟 𝑛 ) )
Detailed syntax breakdown
Step
Hyp
Ref
Expression
0
crtrcl
⊢ t*rec
1
vr
⊢ 𝑟
2
cvv
⊢ V
3
vn
⊢ 𝑛
4
cn0
⊢ ℕ0
5
1
cv
⊢ 𝑟
6
crelexp
⊢ ↑𝑟
7
3
cv
⊢ 𝑛
8
5 7 6
co
⊢ ( 𝑟 ↑𝑟 𝑛 )
9
3 4 8
ciun
⊢ ∪ 𝑛 ∈ ℕ0 ( 𝑟 ↑𝑟 𝑛 )
10
1 2 9
cmpt
⊢ ( 𝑟 ∈ V ↦ ∪ 𝑛 ∈ ℕ0 ( 𝑟 ↑𝑟 𝑛 ) )
11
0 10
wceq
⊢ t*rec = ( 𝑟 ∈ V ↦ ∪ 𝑛 ∈ ℕ0 ( 𝑟 ↑𝑟 𝑛 ) )