Theorem rappsabs | index | src |

theorem rappsabs (a: nat) {x: nat} (A: set x): $ (S\ x, A) @' a == S[a / x] A $;
StepHypRefExpression
1 bitr
(a1 e. (S\ x, A) @' a <-> a, a1 e. S\ x, A) -> (a, a1 e. S\ x, A <-> a1 e. S[a / x] A) -> (a1 e. (S\ x, A) @' a <-> a1 e. S[a / x] A)
2 elrapp
a1 e. (S\ x, A) @' a <-> a, a1 e. S\ x, A
3 1, 2 ax_mp
(a, a1 e. S\ x, A <-> a1 e. S[a / x] A) -> (a1 e. (S\ x, A) @' a <-> a1 e. S[a / x] A)
4 elsabs
a, a1 e. S\ x, A <-> a1 e. S[a / x] A
5 3, 4 ax_mp
a1 e. (S\ x, A) @' a <-> a1 e. S[a / x] A
6 5 ax_gen
A. a1 (a1 e. (S\ x, A) @' a <-> a1 e. S[a / x] A)
7 6 conv eqs
(S\ x, A) @' a == S[a / x] A

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)