Description: Deduction conjoining antecedent to right of consequent in nested implication. (Contributed by NM, 15-Aug-1994) (Proof shortened by Wolf Lammen, 7-Dec-2012)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | anc2ri.1 | ||
| Assertion | anc2ri |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | anc2ri.1 | ||
| 2 | id | ||
| 3 | 1 2 | jctird |