| Step |
Hyp |
Ref |
Expression |
| 1 |
|
2z |
|- 2 e. ZZ |
| 2 |
|
eluzelz |
|- ( N e. ( ZZ>= ` 6 ) -> N e. ZZ ) |
| 3 |
|
dvdsmul2 |
|- ( ( 2 e. ZZ /\ N e. ZZ ) -> N || ( 2 x. N ) ) |
| 4 |
1 2 3
|
sylancr |
|- ( N e. ( ZZ>= ` 6 ) -> N || ( 2 x. N ) ) |
| 5 |
4
|
3ad2ant1 |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> N || ( 2 x. N ) ) |
| 6 |
|
elfzoelz |
|- ( A e. ( 2 ..^ N ) -> A e. ZZ ) |
| 7 |
6
|
zcnd |
|- ( A e. ( 2 ..^ N ) -> A e. CC ) |
| 8 |
|
2cnd |
|- ( A e. ( 2 ..^ N ) -> 2 e. CC ) |
| 9 |
7 8 7
|
mul12d |
|- ( A e. ( 2 ..^ N ) -> ( A x. ( 2 x. A ) ) = ( 2 x. ( A x. A ) ) ) |
| 10 |
9
|
3ad2ant2 |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> ( A x. ( 2 x. A ) ) = ( 2 x. ( A x. A ) ) ) |
| 11 |
|
simp3 |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> N = ( A ^ 2 ) ) |
| 12 |
7
|
sqvald |
|- ( A e. ( 2 ..^ N ) -> ( A ^ 2 ) = ( A x. A ) ) |
| 13 |
12
|
3ad2ant2 |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> ( A ^ 2 ) = ( A x. A ) ) |
| 14 |
11 13
|
eqtr2d |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> ( A x. A ) = N ) |
| 15 |
14
|
oveq2d |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> ( 2 x. ( A x. A ) ) = ( 2 x. N ) ) |
| 16 |
10 15
|
eqtrd |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> ( A x. ( 2 x. A ) ) = ( 2 x. N ) ) |
| 17 |
5 16
|
breqtrrd |
|- ( ( N e. ( ZZ>= ` 6 ) /\ A e. ( 2 ..^ N ) /\ N = ( A ^ 2 ) ) -> N || ( A x. ( 2 x. A ) ) ) |