Metamath Proof Explorer


Theorem iprodmul

Description: Multiplication of infinite sums. (Contributed by Scott Fenton, 18-Dec-2017)

Ref Expression
Hypotheses iprodmul.1 Z = M
iprodmul.2 φ M
iprodmul.3 φ n Z y y 0 seq n × F y
iprodmul.4 φ k Z F k = A
iprodmul.5 φ k Z A
iprodmul.6 φ m Z z z 0 seq m × G z
iprodmul.7 φ k Z G k = B
iprodmul.8 φ k Z B
Assertion iprodmul φ k Z A B = k Z A k Z B

Proof

Step Hyp Ref Expression
1 iprodmul.1 Z = M
2 iprodmul.2 φ M
3 iprodmul.3 φ n Z y y 0 seq n × F y
4 iprodmul.4 φ k Z F k = A
5 iprodmul.5 φ k Z A
6 iprodmul.6 φ m Z z z 0 seq m × G z
7 iprodmul.7 φ k Z G k = B
8 iprodmul.8 φ k Z B
9 4 5 eqeltrd φ k Z F k
10 7 8 eqeltrd φ k Z G k
11 fveq2 a = k F a = F k
12 fveq2 a = k G a = G k
13 11 12 oveq12d a = k F a G a = F k G k
14 eqid a Z F a G a = a Z F a G a
15 ovex F k G k V
16 13 14 15 fvmpt k Z a Z F a G a k = F k G k
17 16 adantl φ k Z a Z F a G a k = F k G k
18 1 3 9 6 10 17 ntrivcvgmul φ p Z w w 0 seq p × a Z F a G a w
19 fveq2 m = a F m = F a
20 fveq2 m = a G m = G a
21 19 20 oveq12d m = a F m G m = F a G a
22 21 cbvmptv m Z F m G m = a Z F a G a
23 seqeq3 m Z F m G m = a Z F a G a seq p × m Z F m G m = seq p × a Z F a G a
24 22 23 ax-mp seq p × m Z F m G m = seq p × a Z F a G a
25 24 breq1i seq p × m Z F m G m w seq p × a Z F a G a w
26 25 anbi2i w 0 seq p × m Z F m G m w w 0 seq p × a Z F a G a w
27 26 exbii w w 0 seq p × m Z F m G m w w w 0 seq p × a Z F a G a w
28 27 rexbii p Z w w 0 seq p × m Z F m G m w p Z w w 0 seq p × a Z F a G a w
29 18 28 sylibr φ p Z w w 0 seq p × m Z F m G m w
30 eqid m Z F m G m = m Z F m G m
31 fveq2 m = k F m = F k
32 fveq2 m = k G m = G k
33 31 32 oveq12d m = k F m G m = F k G k
34 simpr φ k Z k Z
35 9 10 mulcld φ k Z F k G k
36 30 33 34 35 fvmptd3 φ k Z m Z F m G m k = F k G k
37 4 7 oveq12d φ k Z F k G k = A B
38 36 37 eqtrd φ k Z m Z F m G m k = A B
39 5 8 mulcld φ k Z A B
40 1 2 3 4 5 iprodclim2 φ seq M × F k Z A
41 seqex seq M × m Z F m G m V
42 41 a1i φ seq M × m Z F m G m V
43 1 2 6 7 8 iprodclim2 φ seq M × G k Z B
44 1 2 9 prodf φ seq M × F : Z
45 44 ffvelrnda φ j Z seq M × F j
46 1 2 10 prodf φ seq M × G : Z
47 46 ffvelrnda φ j Z seq M × G j
48 simpr φ j Z j Z
49 48 1 eleqtrdi φ j Z j M
50 elfzuz k M j k M
51 50 1 eleqtrrdi k M j k Z
52 51 9 sylan2 φ k M j F k
53 52 adantlr φ j Z k M j F k
54 51 10 sylan2 φ k M j G k
55 54 adantlr φ j Z k M j G k
56 36 adantlr φ j Z k Z m Z F m G m k = F k G k
57 51 56 sylan2 φ j Z k M j m Z F m G m k = F k G k
58 49 53 55 57 prodfmul φ j Z seq M × m Z F m G m j = seq M × F j seq M × G j
59 1 2 40 42 43 45 47 58 climmul φ seq M × m Z F m G m k Z A k Z B
60 1 2 29 38 39 59 iprodclim φ k Z A B = k Z A k Z B