Theorem ballotlemscr

Description: The image of ( RC ) by ( SC ) . (Contributed by Thierry Arnoux, 21-Apr-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 = ( 𝑐 ∈ 𝑂 ↦ ( 𝑖 ∈ ℤ ↦ ( ( ♯ ‘ ( ( 1 ... 𝑖 ) ∩ 𝑐 ) ) − ( ♯ ‘ ( ( 1 ... 𝑖 ) ∖ 𝑐 ) ) ) ) )
	ballotth.e	⊢ 𝐸 = { 𝑐 ∈ 𝑂 ∣ ∀ 𝑖 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) 0 < ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 ) }
	ballotth.mgtn	⊢ 𝑁 < 𝑀
	ballotth.i	⊢ 𝐼 = ( 𝑐 ∈ ( 𝑂 ∖ 𝐸 ) ↦ inf ( { 𝑘 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ∣ ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑘 ) = 0 } , ℝ , < ) )
	ballotth.s	⊢ 𝑆 = ( 𝑐 ∈ ( 𝑂 ∖ 𝐸 ) ↦ ( 𝑖 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ↦ if ( 𝑖 ≤ ( 𝐼 ‘ 𝑐 ) , ( ( ( 𝐼 ‘ 𝑐 ) + 1 ) − 𝑖 ) , 𝑖 ) ) )
	ballotth.r	⊢ 𝑅 = ( 𝑐 ∈ ( 𝑂 ∖ 𝐸 ) ↦ ( ( 𝑆 ‘ 𝑐 ) “ 𝑐 ) )
Assertion	ballotlemscr	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( ( 𝑆 ‘ 𝐶 ) “ ( 𝑅 ‘ 𝐶 ) ) = 𝐶 )

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 = ( 𝑐 ∈ 𝑂 ↦ ( 𝑖 ∈ ℤ ↦ ( ( ♯ ‘ ( ( 1 ... 𝑖 ) ∩ 𝑐 ) ) − ( ♯ ‘ ( ( 1 ... 𝑖 ) ∖ 𝑐 ) ) ) ) )
6		ballotth.e	⊢ 𝐸 = { 𝑐 ∈ 𝑂 ∣ ∀ 𝑖 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) 0 < ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑖 ) }
7		ballotth.mgtn	⊢ 𝑁 < 𝑀
8		ballotth.i	⊢ 𝐼 = ( 𝑐 ∈ ( 𝑂 ∖ 𝐸 ) ↦ inf ( { 𝑘 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ∣ ( ( 𝐹 ‘ 𝑐 ) ‘ 𝑘 ) = 0 } , ℝ , < ) )
9		ballotth.s	⊢ 𝑆 = ( 𝑐 ∈ ( 𝑂 ∖ 𝐸 ) ↦ ( 𝑖 ∈ ( 1 ... ( 𝑀 + 𝑁 ) ) ↦ if ( 𝑖 ≤ ( 𝐼 ‘ 𝑐 ) , ( ( ( 𝐼 ‘ 𝑐 ) + 1 ) − 𝑖 ) , 𝑖 ) ) )
10		ballotth.r	⊢ 𝑅 = ( 𝑐 ∈ ( 𝑂 ∖ 𝐸 ) ↦ ( ( 𝑆 ‘ 𝑐 ) “ 𝑐 ) )
11	1 2 3 4 5 6 7 8 9 10	ballotlemrval	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( 𝑅 ‘ 𝐶 ) = ( ( 𝑆 ‘ 𝐶 ) “ 𝐶 ) )
12	11	imaeq2d	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( ( 𝑆 ‘ 𝐶 ) “ ( 𝑅 ‘ 𝐶 ) ) = ( ( 𝑆 ‘ 𝐶 ) “ ( ( 𝑆 ‘ 𝐶 ) “ 𝐶 ) ) )
13	1 2 3 4 5 6 7 8 9	ballotlemsf1o	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( ( 𝑆 ‘ 𝐶 ) : ( 1 ... ( 𝑀 + 𝑁 ) ) –1-1-onto→ ( 1 ... ( 𝑀 + 𝑁 ) ) ∧ ◡ ( 𝑆 ‘ 𝐶 ) = ( 𝑆 ‘ 𝐶 ) ) )
14	13	simprd	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ◡ ( 𝑆 ‘ 𝐶 ) = ( 𝑆 ‘ 𝐶 ) )
15	14	imaeq1d	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( ◡ ( 𝑆 ‘ 𝐶 ) “ ( ( 𝑆 ‘ 𝐶 ) “ 𝐶 ) ) = ( ( 𝑆 ‘ 𝐶 ) “ ( ( 𝑆 ‘ 𝐶 ) “ 𝐶 ) ) )
16	13	simpld	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( 𝑆 ‘ 𝐶 ) : ( 1 ... ( 𝑀 + 𝑁 ) ) –1-1-onto→ ( 1 ... ( 𝑀 + 𝑁 ) ) )
17		f1of1	⊢ ( ( 𝑆 ‘ 𝐶 ) : ( 1 ... ( 𝑀 + 𝑁 ) ) –1-1-onto→ ( 1 ... ( 𝑀 + 𝑁 ) ) → ( 𝑆 ‘ 𝐶 ) : ( 1 ... ( 𝑀 + 𝑁 ) ) –1-1→ ( 1 ... ( 𝑀 + 𝑁 ) ) )
18	16 17	syl	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( 𝑆 ‘ 𝐶 ) : ( 1 ... ( 𝑀 + 𝑁 ) ) –1-1→ ( 1 ... ( 𝑀 + 𝑁 ) ) )
19		eldifi	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → 𝐶 ∈ 𝑂 )
20	1 2 3	ballotlemelo	⊢ ( 𝐶 ∈ 𝑂 ↔ ( 𝐶 ⊆ ( 1 ... ( 𝑀 + 𝑁 ) ) ∧ ( ♯ ‘ 𝐶 ) = 𝑀 ) )
21	20	simplbi	⊢ ( 𝐶 ∈ 𝑂 → 𝐶 ⊆ ( 1 ... ( 𝑀 + 𝑁 ) ) )
22	19 21	syl	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → 𝐶 ⊆ ( 1 ... ( 𝑀 + 𝑁 ) ) )
23		f1imacnv	⊢ ( ( ( 𝑆 ‘ 𝐶 ) : ( 1 ... ( 𝑀 + 𝑁 ) ) –1-1→ ( 1 ... ( 𝑀 + 𝑁 ) ) ∧ 𝐶 ⊆ ( 1 ... ( 𝑀 + 𝑁 ) ) ) → ( ◡ ( 𝑆 ‘ 𝐶 ) “ ( ( 𝑆 ‘ 𝐶 ) “ 𝐶 ) ) = 𝐶 )
24	18 22 23	syl2anc	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( ◡ ( 𝑆 ‘ 𝐶 ) “ ( ( 𝑆 ‘ 𝐶 ) “ 𝐶 ) ) = 𝐶 )
25	12 15 24	3eqtr2d	⊢ ( 𝐶 ∈ ( 𝑂 ∖ 𝐸 ) → ( ( 𝑆 ‘ 𝐶 ) “ ( 𝑅 ‘ 𝐶 ) ) = 𝐶 )