| Step | Hyp | Ref | Expression | 
						
							| 1 |  | zpnn0elfzo |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> ( Z + N ) e. ( Z ..^ ( ( Z + N ) + 1 ) ) ) | 
						
							| 2 |  | zcn |  |-  ( Z e. ZZ -> Z e. CC ) | 
						
							| 3 | 2 | adantr |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> Z e. CC ) | 
						
							| 4 |  | nn0cn |  |-  ( N e. NN0 -> N e. CC ) | 
						
							| 5 | 4 | adantl |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> N e. CC ) | 
						
							| 6 |  | 1cnd |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> 1 e. CC ) | 
						
							| 7 | 3 5 6 | addassd |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> ( ( Z + N ) + 1 ) = ( Z + ( N + 1 ) ) ) | 
						
							| 8 | 7 | oveq2d |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> ( Z ..^ ( ( Z + N ) + 1 ) ) = ( Z ..^ ( Z + ( N + 1 ) ) ) ) | 
						
							| 9 | 1 8 | eleqtrd |  |-  ( ( Z e. ZZ /\ N e. NN0 ) -> ( Z + N ) e. ( Z ..^ ( Z + ( N + 1 ) ) ) ) |