Theorem addSass | index | src |

theorem addSass (a b: nat): $ suc a + b = a + suc b $;
StepHypRefExpression
1 eqtr4
suc a + b = suc (a + b) -> a + suc b = suc (a + b) -> suc a + b = a + suc b
2 addS1
suc a + b = suc (a + b)
3 1, 2 ax_mp
a + suc b = suc (a + b) -> suc a + b = a + suc b
4 addS2
a + suc b = suc (a + b)
5 3, 4 ax_mp
suc a + b = a + suc b

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp, itru), axs_pred_calc (ax_gen, ax_4, ax_5, ax_6, ax_7, ax_10, ax_11, ax_12), axs_peano (peano2, peano5, addeq, add0, addS)