Metamath Proof Explorer


Theorem dprdlub

Description: The direct product is smaller than any subgroup which contains the factors. (Contributed by Mario Carneiro, 25-Apr-2016)

Ref Expression
Hypotheses dprdlub.1 φ G dom DProd S
dprdlub.2 φ dom S = I
dprdlub.3 φ T SubGrp G
dprdlub.4 φ k I S k T
Assertion dprdlub φ G DProd S T

Proof

Step Hyp Ref Expression
1 dprdlub.1 φ G dom DProd S
2 dprdlub.2 φ dom S = I
3 dprdlub.3 φ T SubGrp G
4 dprdlub.4 φ k I S k T
5 eqid 0 G = 0 G
6 eqid h i I S i | finSupp 0 G h = h i I S i | finSupp 0 G h
7 5 6 dprdval G dom DProd S dom S = I G DProd S = ran f h i I S i | finSupp 0 G h G f
8 1 2 7 syl2anc φ G DProd S = ran f h i I S i | finSupp 0 G h G f
9 eqid Cntz G = Cntz G
10 1 adantr φ f h i I S i | finSupp 0 G h G dom DProd S
11 dprdgrp G dom DProd S G Grp
12 grpmnd G Grp G Mnd
13 10 11 12 3syl φ f h i I S i | finSupp 0 G h G Mnd
14 1 2 dprddomcld φ I V
15 14 adantr φ f h i I S i | finSupp 0 G h I V
16 3 adantr φ f h i I S i | finSupp 0 G h T SubGrp G
17 subgsubm T SubGrp G T SubMnd G
18 16 17 syl φ f h i I S i | finSupp 0 G h T SubMnd G
19 2 adantr φ f h i I S i | finSupp 0 G h dom S = I
20 simpr φ f h i I S i | finSupp 0 G h f h i I S i | finSupp 0 G h
21 eqid Base G = Base G
22 6 10 19 20 21 dprdff φ f h i I S i | finSupp 0 G h f : I Base G
23 22 ffnd φ f h i I S i | finSupp 0 G h f Fn I
24 4 adantlr φ f h i I S i | finSupp 0 G h k I S k T
25 6 10 19 20 dprdfcl φ f h i I S i | finSupp 0 G h k I f k S k
26 24 25 sseldd φ f h i I S i | finSupp 0 G h k I f k T
27 26 ralrimiva φ f h i I S i | finSupp 0 G h k I f k T
28 ffnfv f : I T f Fn I k I f k T
29 23 27 28 sylanbrc φ f h i I S i | finSupp 0 G h f : I T
30 6 10 19 20 9 dprdfcntz φ f h i I S i | finSupp 0 G h ran f Cntz G ran f
31 6 10 19 20 dprdffsupp φ f h i I S i | finSupp 0 G h finSupp 0 G f
32 5 9 13 15 18 29 30 31 gsumzsubmcl φ f h i I S i | finSupp 0 G h G f T
33 32 fmpttd φ f h i I S i | finSupp 0 G h G f : h i I S i | finSupp 0 G h T
34 33 frnd φ ran f h i I S i | finSupp 0 G h G f T
35 8 34 eqsstrd φ G DProd S T