| Step | Hyp | Ref | Expression | 
						
							| 1 |  | metakunt31.1 | ⊢ ( 𝜑  →  𝑀  ∈  ℕ ) | 
						
							| 2 |  | metakunt31.2 | ⊢ ( 𝜑  →  𝐼  ∈  ℕ ) | 
						
							| 3 |  | metakunt31.3 | ⊢ ( 𝜑  →  𝐼  ≤  𝑀 ) | 
						
							| 4 |  | metakunt31.4 | ⊢ ( 𝜑  →  𝑋  ∈  ( 1 ... 𝑀 ) ) | 
						
							| 5 |  | metakunt31.5 | ⊢ 𝐴  =  ( 𝑥  ∈  ( 1 ... 𝑀 )  ↦  if ( 𝑥  =  𝐼 ,  𝑀 ,  if ( 𝑥  <  𝐼 ,  𝑥 ,  ( 𝑥  −  1 ) ) ) ) | 
						
							| 6 |  | metakunt31.6 | ⊢ 𝐵  =  ( 𝑧  ∈  ( 1 ... 𝑀 )  ↦  if ( 𝑧  =  𝑀 ,  𝑀 ,  if ( 𝑧  <  𝐼 ,  ( 𝑧  +  ( 𝑀  −  𝐼 ) ) ,  ( 𝑧  +  ( 1  −  𝐼 ) ) ) ) ) | 
						
							| 7 |  | metakunt31.7 | ⊢ 𝐶  =  ( 𝑦  ∈  ( 1 ... 𝑀 )  ↦  if ( 𝑦  =  𝑀 ,  𝐼 ,  if ( 𝑦  <  𝐼 ,  𝑦 ,  ( 𝑦  +  1 ) ) ) ) | 
						
							| 8 |  | metakunt31.8 | ⊢ 𝐺  =  if ( 𝐼  ≤  ( 𝑋  +  ( 𝑀  −  𝐼 ) ) ,  1 ,  0 ) | 
						
							| 9 |  | metakunt31.9 | ⊢ 𝐻  =  if ( 𝐼  ≤  ( 𝑋  −  𝐼 ) ,  1 ,  0 ) | 
						
							| 10 |  | metakunt31.10 | ⊢ 𝑅  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) | 
						
							| 11 | 1 | adantr | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  𝑀  ∈  ℕ ) | 
						
							| 12 | 2 | adantr | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  𝐼  ∈  ℕ ) | 
						
							| 13 | 3 | adantr | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  𝐼  ≤  𝑀 ) | 
						
							| 14 |  | simpr | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  𝑋  =  𝐼 ) | 
						
							| 15 | 11 12 13 5 7 6 14 | metakunt26 | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑋 ) | 
						
							| 16 | 14 | iftrued | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  𝑋 ) | 
						
							| 17 | 16 | eqcomd | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  𝑋  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) ) | 
						
							| 18 | 15 17 | eqtrd | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) ) | 
						
							| 19 | 10 | eqcomi | ⊢ if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  𝑅 | 
						
							| 20 | 19 | a1i | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  𝑅 ) | 
						
							| 21 | 18 20 | eqtrd | ⊢ ( ( 𝜑  ∧  𝑋  =  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) | 
						
							| 22 | 1 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  𝑀  ∈  ℕ ) | 
						
							| 23 | 2 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  𝐼  ∈  ℕ ) | 
						
							| 24 | 3 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  𝐼  ≤  𝑀 ) | 
						
							| 25 | 4 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  𝑋  ∈  ( 1 ... 𝑀 ) ) | 
						
							| 26 |  | simp2 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  ¬  𝑋  =  𝐼 ) | 
						
							| 27 |  | simp3 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  𝑋  <  𝐼 ) | 
						
							| 28 | 22 23 24 25 5 6 26 27 7 8 | metakunt29 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ) | 
						
							| 29 | 26 | iffalsed | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) | 
						
							| 30 | 27 | iftrued | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) )  =  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ) | 
						
							| 31 | 29 30 | eqtrd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ) | 
						
							| 32 | 31 | eqcomd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 )  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) ) | 
						
							| 33 | 28 32 | eqtrd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) ) | 
						
							| 34 | 19 | a1i | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  𝑅 ) | 
						
							| 35 | 33 34 | eqtrd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) | 
						
							| 36 | 35 | 3expa | ⊢ ( ( ( 𝜑  ∧  ¬  𝑋  =  𝐼 )  ∧  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) | 
						
							| 37 | 1 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  𝑀  ∈  ℕ ) | 
						
							| 38 | 2 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  𝐼  ∈  ℕ ) | 
						
							| 39 | 3 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  𝐼  ≤  𝑀 ) | 
						
							| 40 | 4 | 3ad2ant1 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  𝑋  ∈  ( 1 ... 𝑀 ) ) | 
						
							| 41 |  | simp2 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  ¬  𝑋  =  𝐼 ) | 
						
							| 42 |  | simp3 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  ¬  𝑋  <  𝐼 ) | 
						
							| 43 | 37 38 39 40 5 6 41 42 7 9 | metakunt30 | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) | 
						
							| 44 | 41 | iffalsed | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) | 
						
							| 45 | 42 | iffalsed | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) )  =  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) | 
						
							| 46 | 44 45 | eqtrd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) | 
						
							| 47 | 46 | eqcomd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  ( ( 𝑋  −  𝐼 )  +  𝐻 )  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) ) | 
						
							| 48 | 43 47 | eqtrd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) ) ) | 
						
							| 49 | 19 | a1i | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  if ( 𝑋  =  𝐼 ,  𝑋 ,  if ( 𝑋  <  𝐼 ,  ( ( 𝑋  +  ( 𝑀  −  𝐼 ) )  +  𝐺 ) ,  ( ( 𝑋  −  𝐼 )  +  𝐻 ) ) )  =  𝑅 ) | 
						
							| 50 | 48 49 | eqtrd | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼  ∧  ¬  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) | 
						
							| 51 | 50 | 3expa | ⊢ ( ( ( 𝜑  ∧  ¬  𝑋  =  𝐼 )  ∧  ¬  𝑋  <  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) | 
						
							| 52 | 36 51 | pm2.61dan | ⊢ ( ( 𝜑  ∧  ¬  𝑋  =  𝐼 )  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) | 
						
							| 53 | 21 52 | pm2.61dan | ⊢ ( 𝜑  →  ( 𝐶 ‘ ( 𝐵 ‘ ( 𝐴 ‘ 𝑋 ) ) )  =  𝑅 ) |