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Description: Define a subring of a non-unital ring as a set of elements that is a non-unital ring in its own right. In this section, a subring of a non-unital ring is simply called "subring", unless it causes any ambiguity with SubRing . (Contributed by AV, 14-Feb-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-subrng |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | csubrng | ||
| 1 | vw | ||
| 2 | crng | ||
| 3 | vs | ||
| 4 | cbs | ||
| 5 | 1 | cv | |
| 6 | 5 4 | cfv | |
| 7 | 6 | cpw | |
| 8 | cress | ||
| 9 | 3 | cv | |
| 10 | 5 9 8 | co | |
| 11 | 10 2 | wcel | |
| 12 | 11 3 7 | crab | |
| 13 | 1 2 12 | cmpt | |
| 14 | 0 13 | wceq |