| Step | Hyp | Ref | Expression | 
						
							| 1 |  | smup1.a | ⊢ ( 𝜑  →  𝐴  ⊆  ℕ0 ) | 
						
							| 2 |  | smup1.b | ⊢ ( 𝜑  →  𝐵  ⊆  ℕ0 ) | 
						
							| 3 |  | smup1.n | ⊢ ( 𝜑  →  𝑁  ∈  ℕ0 ) | 
						
							| 4 |  | eqid | ⊢ seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) )  =  seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) ) | 
						
							| 5 | 1 2 4 3 | smupp1 | ⊢ ( 𝜑  →  ( seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) ) ‘ ( 𝑁  +  1 ) )  =  ( ( seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) ) ‘ 𝑁 )  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑁  ∈  𝐴  ∧  ( 𝑛  −  𝑁 )  ∈  𝐵 ) } ) ) | 
						
							| 6 |  | peano2nn0 | ⊢ ( 𝑁  ∈  ℕ0  →  ( 𝑁  +  1 )  ∈  ℕ0 ) | 
						
							| 7 | 3 6 | syl | ⊢ ( 𝜑  →  ( 𝑁  +  1 )  ∈  ℕ0 ) | 
						
							| 8 | 1 2 4 7 | smupval | ⊢ ( 𝜑  →  ( seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) ) ‘ ( 𝑁  +  1 ) )  =  ( ( 𝐴  ∩  ( 0 ..^ ( 𝑁  +  1 ) ) )  smul  𝐵 ) ) | 
						
							| 9 | 1 2 4 3 | smupval | ⊢ ( 𝜑  →  ( seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) ) ‘ 𝑁 )  =  ( ( 𝐴  ∩  ( 0 ..^ 𝑁 ) )  smul  𝐵 ) ) | 
						
							| 10 | 9 | oveq1d | ⊢ ( 𝜑  →  ( ( seq 0 ( ( 𝑝  ∈  𝒫  ℕ0 ,  𝑚  ∈  ℕ0  ↦  ( 𝑝  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑚  ∈  𝐴  ∧  ( 𝑛  −  𝑚 )  ∈  𝐵 ) } ) ) ,  ( 𝑛  ∈  ℕ0  ↦  if ( 𝑛  =  0 ,  ∅ ,  ( 𝑛  −  1 ) ) ) ) ‘ 𝑁 )  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑁  ∈  𝐴  ∧  ( 𝑛  −  𝑁 )  ∈  𝐵 ) } )  =  ( ( ( 𝐴  ∩  ( 0 ..^ 𝑁 ) )  smul  𝐵 )  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑁  ∈  𝐴  ∧  ( 𝑛  −  𝑁 )  ∈  𝐵 ) } ) ) | 
						
							| 11 | 5 8 10 | 3eqtr3d | ⊢ ( 𝜑  →  ( ( 𝐴  ∩  ( 0 ..^ ( 𝑁  +  1 ) ) )  smul  𝐵 )  =  ( ( ( 𝐴  ∩  ( 0 ..^ 𝑁 ) )  smul  𝐵 )  sadd  { 𝑛  ∈  ℕ0  ∣  ( 𝑁  ∈  𝐴  ∧  ( 𝑛  −  𝑁 )  ∈  𝐵 ) } ) ) |