theorem znsubid (m: nat): $ m -ZN m = 0 $;
    
      
        | Step | Hyp | Ref | Expression | 
|---|
        
          | 1 |  | eqtr | m -ZN m = b0 (m - m) -> b0 (m - m) = 0 -> m -ZN m = 0 | 
        
          | 2 |  | znsubpos | m <= m -> m -ZN m = b0 (m - m) | 
        
          | 3 |  | leid | m <= m | 
        
          | 4 | 2, 3 | ax_mp | m -ZN m = b0 (m - m) | 
        
          | 5 | 1, 4 | ax_mp | b0 (m - m) = 0 -> m -ZN m = 0 | 
        
          | 6 |  | eqtr | b0 (m - m) = b0 0 -> b0 0 = 0 -> b0 (m - m) = 0 | 
        
          | 7 |  | b0eq | m - m = 0 -> b0 (m - m) = b0 0 | 
        
          | 8 |  | subid | m - m = 0 | 
        
          | 9 | 7, 8 | ax_mp | b0 (m - m) = b0 0 | 
        
          | 10 | 6, 9 | ax_mp | b0 0 = 0 -> b0 (m - m) = 0 | 
        
          | 11 |  | b00 | b0 0 = 0 | 
        
          | 12 | 10, 11 | ax_mp | b0 (m - m) = 0 | 
        
          | 13 | 5, 12 | ax_mp | m -ZN m = 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),
    
axs_peano
     (peano1,
      peano2,
      peano5,
      addeq,
      add0,
      addS)