Metamath Proof Explorer


Theorem ballotlemi1

Description: The first tie cannot be reached at the first pick. (Contributed by Thierry Arnoux, 12-Mar-2017)

Ref Expression
Hypotheses ballotth.m 𝑀 ∈ ℕ
ballotth.n 𝑁 ∈ ℕ
ballotth.o 𝑂 = { 𝑐 ∈ 𝒫 ( 1 ... ( 𝑀 + 𝑁 ) ) ∣ ( ♯ ‘ 𝑐 ) = 𝑀 }
ballotth.p 𝑃 = ( 𝑥 ∈ 𝒫 𝑂 ↦ ( ( ♯ ‘ 𝑥 ) / ( ♯ ‘ 𝑂 ) ) )
ballotth.f 𝐹 = ( 𝑐𝑂 ↦ ( 𝑖 ∈ ℤ ↦ ( ( ♯ ‘ ( ( 1 ... 𝑖 ) ∩ 𝑐 ) ) − ( ♯ ‘ ( ( 1 ... 𝑖 ) ∖ 𝑐 ) ) ) ) )
ballotth.e 𝐸 = { 𝑐𝑂 ∣ ∀ 𝑖 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) 0 < ( ( 𝐹𝑐 ) ‘ 𝑖 ) }
ballotth.mgtn 𝑁 < 𝑀
ballotth.i 𝐼 = ( 𝑐 ∈ ( 𝑂𝐸 ) ↦ inf ( { 𝑘 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ∣ ( ( 𝐹𝑐 ) ‘ 𝑘 ) = 0 } , ℝ , < ) )
Assertion ballotlemi1 ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( 𝐼𝐶 ) ≠ 1 )

Proof

Step Hyp Ref Expression
1 ballotth.m 𝑀 ∈ ℕ
2 ballotth.n 𝑁 ∈ ℕ
3 ballotth.o 𝑂 = { 𝑐 ∈ 𝒫 ( 1 ... ( 𝑀 + 𝑁 ) ) ∣ ( ♯ ‘ 𝑐 ) = 𝑀 }
4 ballotth.p 𝑃 = ( 𝑥 ∈ 𝒫 𝑂 ↦ ( ( ♯ ‘ 𝑥 ) / ( ♯ ‘ 𝑂 ) ) )
5 ballotth.f 𝐹 = ( 𝑐𝑂 ↦ ( 𝑖 ∈ ℤ ↦ ( ( ♯ ‘ ( ( 1 ... 𝑖 ) ∩ 𝑐 ) ) − ( ♯ ‘ ( ( 1 ... 𝑖 ) ∖ 𝑐 ) ) ) ) )
6 ballotth.e 𝐸 = { 𝑐𝑂 ∣ ∀ 𝑖 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) 0 < ( ( 𝐹𝑐 ) ‘ 𝑖 ) }
7 ballotth.mgtn 𝑁 < 𝑀
8 ballotth.i 𝐼 = ( 𝑐 ∈ ( 𝑂𝐸 ) ↦ inf ( { 𝑘 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ∣ ( ( 𝐹𝑐 ) ‘ 𝑘 ) = 0 } , ℝ , < ) )
9 0re 0 ∈ ℝ
10 1re 1 ∈ ℝ
11 9 10 resubcli ( 0 − 1 ) ∈ ℝ
12 0lt1 0 < 1
13 ltsub23 ( ( 0 ∈ ℝ ∧ 1 ∈ ℝ ∧ 0 ∈ ℝ ) → ( ( 0 − 1 ) < 0 ↔ ( 0 − 0 ) < 1 ) )
14 9 10 9 13 mp3an ( ( 0 − 1 ) < 0 ↔ ( 0 − 0 ) < 1 )
15 0m0e0 ( 0 − 0 ) = 0
16 15 breq1i ( ( 0 − 0 ) < 1 ↔ 0 < 1 )
17 14 16 bitr2i ( 0 < 1 ↔ ( 0 − 1 ) < 0 )
18 12 17 mpbi ( 0 − 1 ) < 0
19 11 18 gtneii 0 ≠ ( 0 − 1 )
20 19 nesymi ¬ ( 0 − 1 ) = 0
21 eldifi ( 𝐶 ∈ ( 𝑂𝐸 ) → 𝐶𝑂 )
22 1nn 1 ∈ ℕ
23 22 a1i ( 𝐶 ∈ ( 𝑂𝐸 ) → 1 ∈ ℕ )
24 1 2 3 4 5 21 23 ballotlemfp1 ( 𝐶 ∈ ( 𝑂𝐸 ) → ( ( ¬ 1 ∈ 𝐶 → ( ( 𝐹𝐶 ) ‘ 1 ) = ( ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) − 1 ) ) ∧ ( 1 ∈ 𝐶 → ( ( 𝐹𝐶 ) ‘ 1 ) = ( ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) + 1 ) ) ) )
25 24 simpld ( 𝐶 ∈ ( 𝑂𝐸 ) → ( ¬ 1 ∈ 𝐶 → ( ( 𝐹𝐶 ) ‘ 1 ) = ( ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) − 1 ) ) )
26 25 imp ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( ( 𝐹𝐶 ) ‘ 1 ) = ( ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) − 1 ) )
27 1m1e0 ( 1 − 1 ) = 0
28 27 fveq2i ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) = ( ( 𝐹𝐶 ) ‘ 0 )
29 28 oveq1i ( ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) − 1 ) = ( ( ( 𝐹𝐶 ) ‘ 0 ) − 1 )
30 29 a1i ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( ( ( 𝐹𝐶 ) ‘ ( 1 − 1 ) ) − 1 ) = ( ( ( 𝐹𝐶 ) ‘ 0 ) − 1 ) )
31 1 2 3 4 5 ballotlemfval0 ( 𝐶𝑂 → ( ( 𝐹𝐶 ) ‘ 0 ) = 0 )
32 21 31 syl ( 𝐶 ∈ ( 𝑂𝐸 ) → ( ( 𝐹𝐶 ) ‘ 0 ) = 0 )
33 32 adantr ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( ( 𝐹𝐶 ) ‘ 0 ) = 0 )
34 33 oveq1d ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( ( ( 𝐹𝐶 ) ‘ 0 ) − 1 ) = ( 0 − 1 ) )
35 26 30 34 3eqtrrd ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( 0 − 1 ) = ( ( 𝐹𝐶 ) ‘ 1 ) )
36 35 eqeq1d ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( ( 0 − 1 ) = 0 ↔ ( ( 𝐹𝐶 ) ‘ 1 ) = 0 ) )
37 20 36 mtbii ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ¬ ( ( 𝐹𝐶 ) ‘ 1 ) = 0 )
38 1 2 3 4 5 6 7 8 ballotlemiex ( 𝐶 ∈ ( 𝑂𝐸 ) → ( ( 𝐼𝐶 ) ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ∧ ( ( 𝐹𝐶 ) ‘ ( 𝐼𝐶 ) ) = 0 ) )
39 38 simprd ( 𝐶 ∈ ( 𝑂𝐸 ) → ( ( 𝐹𝐶 ) ‘ ( 𝐼𝐶 ) ) = 0 )
40 39 ad2antrr ( ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) ∧ ( 𝐼𝐶 ) = 1 ) → ( ( 𝐹𝐶 ) ‘ ( 𝐼𝐶 ) ) = 0 )
41 fveqeq2 ( ( 𝐼𝐶 ) = 1 → ( ( ( 𝐹𝐶 ) ‘ ( 𝐼𝐶 ) ) = 0 ↔ ( ( 𝐹𝐶 ) ‘ 1 ) = 0 ) )
42 41 adantl ( ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) ∧ ( 𝐼𝐶 ) = 1 ) → ( ( ( 𝐹𝐶 ) ‘ ( 𝐼𝐶 ) ) = 0 ↔ ( ( 𝐹𝐶 ) ‘ 1 ) = 0 ) )
43 40 42 mpbid ( ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) ∧ ( 𝐼𝐶 ) = 1 ) → ( ( 𝐹𝐶 ) ‘ 1 ) = 0 )
44 37 43 mtand ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ¬ ( 𝐼𝐶 ) = 1 )
45 44 neqned ( ( 𝐶 ∈ ( 𝑂𝐸 ) ∧ ¬ 1 ∈ 𝐶 ) → ( 𝐼𝐶 ) ≠ 1 )