Description: Closure of a group sum in a subgroup. (Contributed by Mario Carneiro, 15-Dec-2014) (Revised by AV, 3-Jun-2019)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | gsumsubgcl.z | |- .0. = ( 0g ` G ) |
|
| gsumsubgcl.g | |- ( ph -> G e. Abel ) |
||
| gsumsubgcl.a | |- ( ph -> A e. V ) |
||
| gsumsubgcl.s | |- ( ph -> S e. ( SubGrp ` G ) ) |
||
| gsumsubgcl.f | |- ( ph -> F : A --> S ) |
||
| gsumsubgcl.w | |- ( ph -> F finSupp .0. ) |
||
| Assertion | gsumsubgcl | |- ( ph -> ( G gsum F ) e. S ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | gsumsubgcl.z | |- .0. = ( 0g ` G ) |
|
| 2 | gsumsubgcl.g | |- ( ph -> G e. Abel ) |
|
| 3 | gsumsubgcl.a | |- ( ph -> A e. V ) |
|
| 4 | gsumsubgcl.s | |- ( ph -> S e. ( SubGrp ` G ) ) |
|
| 5 | gsumsubgcl.f | |- ( ph -> F : A --> S ) |
|
| 6 | gsumsubgcl.w | |- ( ph -> F finSupp .0. ) |
|
| 7 | ablcmn | |- ( G e. Abel -> G e. CMnd ) |
|
| 8 | 2 7 | syl | |- ( ph -> G e. CMnd ) |
| 9 | subgsubm | |- ( S e. ( SubGrp ` G ) -> S e. ( SubMnd ` G ) ) |
|
| 10 | 4 9 | syl | |- ( ph -> S e. ( SubMnd ` G ) ) |
| 11 | 1 8 3 10 5 6 | gsumsubmcl | |- ( ph -> ( G gsum F ) e. S ) |