Theorem leneqd ≪ | index | src | ≫

theorem leneqd (_G: wff) (_l1 _l2: nat):
  $ _G -> _l1 = _l2 $ >
  $ _G -> len _l1 = len _l2 $;

Step	Hyp	Ref	Expression
1		hyp _lh	_G -> _l1 = _l2
2	1	lreceq3d	_G -> lrec 0 (\\ x, \\ z, \ y, suc y) _l1 = lrec 0 (\\ x, \\ z, \ y, suc y) _l2
3	2	conv len	_G -> len _l1 = len _l2

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)