Metamath Proof Explorer


Theorem fz0to4untppr

Description: An integer range from 0 to 4 is the union of a triple and a pair. (Contributed by Alexander van der Vekens, 13-Aug-2017) (Proof shortened by AV, 7-Aug-2025)

Ref Expression
Assertion fz0to4untppr ( 0 ... 4 ) = ( { 0 , 1 , 2 } ∪ { 3 , 4 } )

Proof

Step Hyp Ref Expression
1 2p1e3 ( 2 + 1 ) = 3
2 0z 0 ∈ ℤ
3 3z 3 ∈ ℤ
4 0re 0 ∈ ℝ
5 3re 3 ∈ ℝ
6 3pos 0 < 3
7 4 5 6 ltleii 0 ≤ 3
8 eluz2 ( 3 ∈ ( ℤ ‘ 0 ) ↔ ( 0 ∈ ℤ ∧ 3 ∈ ℤ ∧ 0 ≤ 3 ) )
9 2 3 7 8 mpbir3an 3 ∈ ( ℤ ‘ 0 )
10 1 9 eqeltri ( 2 + 1 ) ∈ ( ℤ ‘ 0 )
11 2z 2 ∈ ℤ
12 4z 4 ∈ ℤ
13 2re 2 ∈ ℝ
14 4re 4 ∈ ℝ
15 2lt4 2 < 4
16 13 14 15 ltleii 2 ≤ 4
17 eluz2 ( 4 ∈ ( ℤ ‘ 2 ) ↔ ( 2 ∈ ℤ ∧ 4 ∈ ℤ ∧ 2 ≤ 4 ) )
18 11 12 16 17 mpbir3an 4 ∈ ( ℤ ‘ 2 )
19 fzsplit2 ( ( ( 2 + 1 ) ∈ ( ℤ ‘ 0 ) ∧ 4 ∈ ( ℤ ‘ 2 ) ) → ( 0 ... 4 ) = ( ( 0 ... 2 ) ∪ ( ( 2 + 1 ) ... 4 ) ) )
20 10 18 19 mp2an ( 0 ... 4 ) = ( ( 0 ... 2 ) ∪ ( ( 2 + 1 ) ... 4 ) )
21 fz0tp ( 0 ... 2 ) = { 0 , 1 , 2 }
22 1 oveq1i ( ( 2 + 1 ) ... 4 ) = ( 3 ... 4 )
23 df-4 4 = ( 3 + 1 )
24 23 oveq2i ( 3 ... 4 ) = ( 3 ... ( 3 + 1 ) )
25 fzpr ( 3 ∈ ℤ → ( 3 ... ( 3 + 1 ) ) = { 3 , ( 3 + 1 ) } )
26 3 25 ax-mp ( 3 ... ( 3 + 1 ) ) = { 3 , ( 3 + 1 ) }
27 3p1e4 ( 3 + 1 ) = 4
28 27 preq2i { 3 , ( 3 + 1 ) } = { 3 , 4 }
29 24 26 28 3eqtri ( 3 ... 4 ) = { 3 , 4 }
30 22 29 eqtri ( ( 2 + 1 ) ... 4 ) = { 3 , 4 }
31 21 30 uneq12i ( ( 0 ... 2 ) ∪ ( ( 2 + 1 ) ... 4 ) ) = ( { 0 , 1 , 2 } ∪ { 3 , 4 } )
32 20 31 eqtri ( 0 ... 4 ) = ( { 0 , 1 , 2 } ∪ { 3 , 4 } )