Theorem zleadd1 | index | src |

theorem zleadd1 (a b c: nat): $ a <=Z b <-> a +Z c <=Z b +Z c $;
StepHypRefExpression
1 noteq
(b <Z a <-> b +Z c <Z a +Z c) -> (~b <Z a <-> ~b +Z c <Z a +Z c)
2 1 conv zle
(b <Z a <-> b +Z c <Z a +Z c) -> (a <=Z b <-> a +Z c <=Z b +Z c)
3 zltadd1
b <Z a <-> b +Z c <Z a +Z c
4 2, 3 ax_mp
a <=Z b <-> a +Z c <=Z b +Z c

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_set (elab, ax_8), axs_the (theid, the0), axs_peano (peano1, peano2, peano5, addeq, muleq, add0, addS, mul0, mulS)