Database
REAL AND COMPLEX NUMBERS
Words over a set
Repeated symbol words
repswsymb
Next ⟩
repsw
Metamath Proof Explorer
Ascii
Unicode
Theorem
repswsymb
Description:
The symbols of a "repeated symbol word".
(Contributed by
AV
, 4-Nov-2018)
Ref
Expression
Assertion
repswsymb
⊢
S
∈
V
∧
N
∈
ℕ
0
∧
I
∈
0
..^
N
→
S
repeatS
N
⁡
I
=
S
Proof
Step
Hyp
Ref
Expression
1
reps
⊢
S
∈
V
∧
N
∈
ℕ
0
→
S
repeatS
N
=
x
∈
0
..^
N
⟼
S
2
1
3adant3
⊢
S
∈
V
∧
N
∈
ℕ
0
∧
I
∈
0
..^
N
→
S
repeatS
N
=
x
∈
0
..^
N
⟼
S
3
eqidd
⊢
S
∈
V
∧
N
∈
ℕ
0
∧
I
∈
0
..^
N
∧
x
=
I
→
S
=
S
4
simp3
⊢
S
∈
V
∧
N
∈
ℕ
0
∧
I
∈
0
..^
N
→
I
∈
0
..^
N
5
simp1
⊢
S
∈
V
∧
N
∈
ℕ
0
∧
I
∈
0
..^
N
→
S
∈
V
6
2
3
4
5
fvmptd
⊢
S
∈
V
∧
N
∈
ℕ
0
∧
I
∈
0
..^
N
→
S
repeatS
N
⁡
I
=
S