Metamath Proof Explorer


Theorem fsumcl2lem

Description: - Lemma for finite sum closures. (The "-" before "Lemma" forces the math content to be displayed in the Statement List - NM 11-Feb-2008.) (Contributed by Mario Carneiro, 3-Jun-2014)

Ref Expression
Hypotheses fsumcllem.1 ⊢ φ → S ⊆ ℂ
fsumcllem.2 ⊢ φ ∧ x ∈ S ∧ y ∈ S → x + y ∈ S
fsumcllem.3 ⊢ φ → A ∈ Fin
fsumcllem.4 ⊢ φ ∧ k ∈ A → B ∈ S
fsumcl2lem.5 ⊢ φ → A ≠ ∅
Assertion fsumcl2lem ⊢ φ → ∑ k ∈ A B ∈ S

Proof

Step Hyp Ref Expression
1 fsumcllem.1 ⊢ φ → S ⊆ ℂ
2 fsumcllem.2 ⊢ φ ∧ x ∈ S ∧ y ∈ S → x + y ∈ S
3 fsumcllem.3 ⊢ φ → A ∈ Fin
4 fsumcllem.4 ⊢ φ ∧ k ∈ A → B ∈ S
5 fsumcl2lem.5 ⊢ φ → A ≠ ∅
6 5 a1d ⊢ φ → ¬ ∑ k ∈ A B ∈ S → A ≠ ∅
7 6 necon4bd ⊢ φ → A = ∅ → ∑ k ∈ A B ∈ S
8 sumfc ⊢ ∑ m ∈ A k ∈ A ⟼ B ⁡ m = ∑ k ∈ A B
9 fveq2 ⊢ m = f ⁡ x → k ∈ A ⟼ B ⁡ m = k ∈ A ⟼ B ⁡ f ⁡ x
10 simprl ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → A ∈ ℕ
11 simprr ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → f : 1 … A ⟶ 1-1 onto A
12 1 ad2antrr ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A ∧ m ∈ A → S ⊆ ℂ
13 4 fmpttd ⊢ φ → k ∈ A ⟼ B : A ⟶ S
14 13 adantr ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → k ∈ A ⟼ B : A ⟶ S
15 14 ffvelcdmda ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A ∧ m ∈ A → k ∈ A ⟼ B ⁡ m ∈ S
16 12 15 sseldd ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A ∧ m ∈ A → k ∈ A ⟼ B ⁡ m ∈ ℂ
17 f1of ⊢ f : 1 … A ⟶ 1-1 onto A → f : 1 … A ⟶ A
18 11 17 syl ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → f : 1 … A ⟶ A
19 fvco3 ⊢ f : 1 … A ⟶ A ∧ x ∈ 1 … A → k ∈ A ⟼ B ∘ f ⁡ x = k ∈ A ⟼ B ⁡ f ⁡ x
20 18 19 sylan ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A ∧ x ∈ 1 … A → k ∈ A ⟼ B ∘ f ⁡ x = k ∈ A ⟼ B ⁡ f ⁡ x
21 9 10 11 16 20 fsum ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → ∑ m ∈ A k ∈ A ⟼ B ⁡ m = seq 1 + k ∈ A ⟼ B ∘ f ⁡ A
22 8 21 eqtr3id ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → ∑ k ∈ A B = seq 1 + k ∈ A ⟼ B ∘ f ⁡ A
23 nnuz ⊢ ℕ = ℤ ≥ 1
24 10 23 eleqtrdi ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → A ∈ ℤ ≥ 1
25 fco ⊢ k ∈ A ⟼ B : A ⟶ S ∧ f : 1 … A ⟶ A → k ∈ A ⟼ B ∘ f : 1 … A ⟶ S
26 14 18 25 syl2anc ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → k ∈ A ⟼ B ∘ f : 1 … A ⟶ S
27 26 ffvelcdmda ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A ∧ x ∈ 1 … A → k ∈ A ⟼ B ∘ f ⁡ x ∈ S
28 2 adantlr ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A ∧ x ∈ S ∧ y ∈ S → x + y ∈ S
29 24 27 28 seqcl ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → seq 1 + k ∈ A ⟼ B ∘ f ⁡ A ∈ S
30 22 29 eqeltrd ⊢ φ ∧ A ∈ ℕ ∧ f : 1 … A ⟶ 1-1 onto A → ∑ k ∈ A B ∈ S
31 30 expr ⊢ φ ∧ A ∈ ℕ → f : 1 … A ⟶ 1-1 onto A → ∑ k ∈ A B ∈ S
32 31 exlimdv ⊢ φ ∧ A ∈ ℕ → ∃ f f : 1 … A ⟶ 1-1 onto A → ∑ k ∈ A B ∈ S
33 32 expimpd ⊢ φ → A ∈ ℕ ∧ ∃ f f : 1 … A ⟶ 1-1 onto A → ∑ k ∈ A B ∈ S
34 fz1f1o ⊢ A ∈ Fin → A = ∅ ∨ A ∈ ℕ ∧ ∃ f f : 1 … A ⟶ 1-1 onto A
35 3 34 syl ⊢ φ → A = ∅ ∨ A ∈ ℕ ∧ ∃ f f : 1 … A ⟶ 1-1 onto A
36 7 33 35 mpjaod ⊢ φ → ∑ k ∈ A B ∈ S