Description: Nonnegative multiple of a group sum. (Contributed by Mario Carneiro, 15-Dec-2014) (Revised by Mario Carneiro, 7-Jan-2015) (Revised by AV, 6-Jun-2019)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | gsummulg.b | |- B = ( Base ` G ) | |
| gsummulg.z | |- .0. = ( 0g ` G ) | ||
| gsummulg.t | |- .x. = ( .g ` G ) | ||
| gsummulg.a | |- ( ph -> A e. V ) | ||
| gsummulg.f | |- ( ( ph /\ k e. A ) -> X e. B ) | ||
| gsummulg.w | |- ( ph -> ( k e. A |-> X ) finSupp .0. ) | ||
| gsummulg.g | |- ( ph -> G e. CMnd ) | ||
| gsummulg.n | |- ( ph -> N e. NN0 ) | ||
| Assertion | gsummulg | |- ( ph -> ( G gsum ( k e. A |-> ( N .x. X ) ) ) = ( N .x. ( G gsum ( k e. A |-> X ) ) ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | gsummulg.b | |- B = ( Base ` G ) | |
| 2 | gsummulg.z | |- .0. = ( 0g ` G ) | |
| 3 | gsummulg.t | |- .x. = ( .g ` G ) | |
| 4 | gsummulg.a | |- ( ph -> A e. V ) | |
| 5 | gsummulg.f | |- ( ( ph /\ k e. A ) -> X e. B ) | |
| 6 | gsummulg.w | |- ( ph -> ( k e. A |-> X ) finSupp .0. ) | |
| 7 | gsummulg.g | |- ( ph -> G e. CMnd ) | |
| 8 | gsummulg.n | |- ( ph -> N e. NN0 ) | |
| 9 | 8 | nn0zd | |- ( ph -> N e. ZZ ) | 
| 10 | 8 | olcd | |- ( ph -> ( G e. Abel \/ N e. NN0 ) ) | 
| 11 | 1 2 3 4 5 6 7 9 10 | gsummulglem | |- ( ph -> ( G gsum ( k e. A |-> ( N .x. X ) ) ) = ( N .x. ( G gsum ( k e. A |-> X ) ) ) ) |