| Step | Hyp | Ref | Expression | 
						
							| 1 |  | nn0z |  |-  ( b e. NN0 -> b e. ZZ ) | 
						
							| 2 | 1 | a1i |  |-  ( D e. ( NN \ []NN ) -> ( b e. NN0 -> b e. ZZ ) ) | 
						
							| 3 | 2 | anim1d |  |-  ( D e. ( NN \ []NN ) -> ( ( b e. NN0 /\ E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) -> ( b e. ZZ /\ E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 4 | 3 | reximdv2 |  |-  ( D e. ( NN \ []NN ) -> ( E. b e. NN0 E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) -> E. b e. ZZ E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) ) | 
						
							| 5 | 4 | anim2d |  |-  ( D e. ( NN \ []NN ) -> ( ( a e. RR /\ E. b e. NN0 E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) -> ( a e. RR /\ E. b e. ZZ E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 6 |  | elpell14qr |  |-  ( D e. ( NN \ []NN ) -> ( a e. ( Pell14QR ` D ) <-> ( a e. RR /\ E. b e. NN0 E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 7 |  | elpell1234qr |  |-  ( D e. ( NN \ []NN ) -> ( a e. ( Pell1234QR ` D ) <-> ( a e. RR /\ E. b e. ZZ E. c e. ZZ ( a = ( b + ( ( sqrt ` D ) x. c ) ) /\ ( ( b ^ 2 ) - ( D x. ( c ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 8 | 5 6 7 | 3imtr4d |  |-  ( D e. ( NN \ []NN ) -> ( a e. ( Pell14QR ` D ) -> a e. ( Pell1234QR ` D ) ) ) | 
						
							| 9 | 8 | ssrdv |  |-  ( D e. ( NN \ []NN ) -> ( Pell14QR ` D ) C_ ( Pell1234QR ` D ) ) |