theorem suceq (a b: nat): $ a = b -> suc a = suc b $;
| Step | Hyp | Ref | Expression |
|---|
| 1 |
|
bi2 |
(suc a = suc b <-> a = b) -> a = b -> suc a = suc b |
| 2 |
|
peano2 |
suc a = suc b <-> a = b |
| 3 |
1, 2 |
ax_mp |
a = b -> suc a = suc b |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_3,
ax_mp),
axs_peano
(peano2)