Metamath Proof Explorer


Definition df-lsm

Description: Define subgroup sum (inner direct product of subgroups). (Contributed by NM, 28-Jan-2014)

Ref Expression
Assertion df-lsm LSSum=wVt𝒫Basew,u𝒫Basewranxt,yux+wy

Detailed syntax breakdown

Step Hyp Ref Expression
0 clsm classLSSum
1 vw setvarw
2 cvv classV
3 vt setvart
4 cbs classBase
5 1 cv setvarw
6 5 4 cfv classBasew
7 6 cpw class𝒫Basew
8 vu setvaru
9 vx setvarx
10 3 cv setvart
11 vy setvary
12 8 cv setvaru
13 9 cv setvarx
14 cplusg class+𝑔
15 5 14 cfv class+w
16 11 cv setvary
17 13 16 15 co classx+wy
18 9 11 10 12 17 cmpo classxt,yux+wy
19 18 crn classranxt,yux+wy
20 3 8 7 7 19 cmpo classt𝒫Basew,u𝒫Basewranxt,yux+wy
21 1 2 20 cmpt classwVt𝒫Basew,u𝒫Basewranxt,yux+wy
22 0 21 wceq wffLSSum=wVt𝒫Basew,u𝒫Basewranxt,yux+wy