Metamath Proof Explorer


Theorem lsmssass

Description: Group sum is associative, subset version (see lsmass ). (Contributed by Thierry Arnoux, 1-Jun-2024)

Ref Expression
Hypotheses lsmssass.p ˙=LSSumG
lsmssass.b B=BaseG
lsmssass.g φGMnd
lsmssass.r φRB
lsmssass.t φTB
lsmssass.u φUB
Assertion lsmssass φR˙T˙U=R˙T˙U

Proof

Step Hyp Ref Expression
1 lsmssass.p ˙=LSSumG
2 lsmssass.b B=BaseG
3 lsmssass.g φGMnd
4 lsmssass.r φRB
5 lsmssass.t φTB
6 lsmssass.u φUB
7 eqid +G=+G
8 2 7 1 lsmvalx GMndRBTBR˙T=ranaR,bTa+Gb
9 3 4 5 8 syl3anc φR˙T=ranaR,bTa+Gb
10 9 rexeqdv φyR˙TcUx=y+GcyranaR,bTa+GbcUx=y+Gc
11 ovex a+GbV
12 11 rgen2w aRbTa+GbV
13 eqid aR,bTa+Gb=aR,bTa+Gb
14 oveq1 y=a+Gby+Gc=a+Gb+Gc
15 14 eqeq2d y=a+Gbx=y+Gcx=a+Gb+Gc
16 15 rexbidv y=a+GbcUx=y+GccUx=a+Gb+Gc
17 13 16 rexrnmpo aRbTa+GbVyranaR,bTa+GbcUx=y+GcaRbTcUx=a+Gb+Gc
18 12 17 ax-mp yranaR,bTa+GbcUx=y+GcaRbTcUx=a+Gb+Gc
19 10 18 bitrdi φyR˙TcUx=y+GcaRbTcUx=a+Gb+Gc
20 2 7 1 lsmvalx GMndTBUBT˙U=ranbT,cUb+Gc
21 3 5 6 20 syl3anc φT˙U=ranbT,cUb+Gc
22 21 rexeqdv φzT˙Ux=a+GzzranbT,cUb+Gcx=a+Gz
23 ovex b+GcV
24 23 rgen2w bTcUb+GcV
25 eqid bT,cUb+Gc=bT,cUb+Gc
26 oveq2 z=b+Gca+Gz=a+Gb+Gc
27 26 eqeq2d z=b+Gcx=a+Gzx=a+Gb+Gc
28 25 27 rexrnmpo bTcUb+GcVzranbT,cUb+Gcx=a+GzbTcUx=a+Gb+Gc
29 24 28 ax-mp zranbT,cUb+Gcx=a+GzbTcUx=a+Gb+Gc
30 22 29 bitrdi φzT˙Ux=a+GzbTcUx=a+Gb+Gc
31 30 adantr φaRzT˙Ux=a+GzbTcUx=a+Gb+Gc
32 3 ad2antrr φaRbTcUGMnd
33 4 ad2antrr φaRbTcURB
34 simplr φaRbTcUaR
35 33 34 sseldd φaRbTcUaB
36 5 ad2antrr φaRbTcUTB
37 simprl φaRbTcUbT
38 36 37 sseldd φaRbTcUbB
39 6 ad2antrr φaRbTcUUB
40 simprr φaRbTcUcU
41 39 40 sseldd φaRbTcUcB
42 2 7 mndass GMndaBbBcBa+Gb+Gc=a+Gb+Gc
43 32 35 38 41 42 syl13anc φaRbTcUa+Gb+Gc=a+Gb+Gc
44 43 eqeq2d φaRbTcUx=a+Gb+Gcx=a+Gb+Gc
45 44 2rexbidva φaRbTcUx=a+Gb+GcbTcUx=a+Gb+Gc
46 31 45 bitr4d φaRzT˙Ux=a+GzbTcUx=a+Gb+Gc
47 46 rexbidva φaRzT˙Ux=a+GzaRbTcUx=a+Gb+Gc
48 19 47 bitr4d φyR˙TcUx=y+GcaRzT˙Ux=a+Gz
49 2 1 lsmssv GMndRBTBR˙TB
50 3 4 5 49 syl3anc φR˙TB
51 2 7 1 lsmelvalx GMndR˙TBUBxR˙T˙UyR˙TcUx=y+Gc
52 3 50 6 51 syl3anc φxR˙T˙UyR˙TcUx=y+Gc
53 2 1 lsmssv GMndTBUBT˙UB
54 3 5 6 53 syl3anc φT˙UB
55 2 7 1 lsmelvalx GMndRBT˙UBxR˙T˙UaRzT˙Ux=a+Gz
56 3 4 54 55 syl3anc φxR˙T˙UaRzT˙Ux=a+Gz
57 48 52 56 3bitr4d φxR˙T˙UxR˙T˙U
58 57 eqrdv φR˙T˙U=R˙T˙U