Theorem sublistAteqd | index | src |

theorem sublistAteqd (_G: wff) (_n1 _n2 _L11 _L12 _L21 _L22: nat):
  $ _G -> _n1 = _n2 $ >
  $ _G -> _L11 = _L12 $ >
  $ _G -> _L21 = _L22 $ >
  $ _G -> (sublistAt _n1 _L11 _L21 <-> sublistAt _n2 _L12 _L22) $;
StepHypRefExpression
1 hyp _L1h
_G -> _L11 = _L12
2 hyp _L2h
_G -> _L21 = _L22
3 2 appendeq1d
_G -> _L21 ++ r = _L22 ++ r
4 3 appendeq2d
_G -> l ++ _L21 ++ r = l ++ _L22 ++ r
5 1, 4 eqeqd
_G -> (_L11 = l ++ _L21 ++ r <-> _L12 = l ++ _L22 ++ r)
6 hyp _nh
_G -> _n1 = _n2
7 6 eqeq2d
_G -> (len l = _n1 <-> len l = _n2)
8 5, 7 aneqd
_G -> (_L11 = l ++ _L21 ++ r /\ len l = _n1 <-> _L12 = l ++ _L22 ++ r /\ len l = _n2)
9 8 exeqd
_G -> (E. r (_L11 = l ++ _L21 ++ r /\ len l = _n1) <-> E. r (_L12 = l ++ _L22 ++ r /\ len l = _n2))
10 9 exeqd
_G -> (E. l E. r (_L11 = l ++ _L21 ++ r /\ len l = _n1) <-> E. l E. r (_L12 = l ++ _L22 ++ r /\ len l = _n2))
11 10 conv sublistAt
_G -> (sublistAt _n1 _L11 _L21 <-> sublistAt _n2 _L12 _L22)

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 (peano2, addeq, muleq)