Theorem elArray0 ≪ | index | src | ≫ 

theorem elArray0 (A: set): $ 0 e. Array A 0 $;
StepHypRefExpression
1 elArray02 
0 e. Array A 0 <-> 0 = 0
2 eqid 
0 = 0
3 1, 2 mpbir 
0 e. Array A 0

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)