Step |
Hyp |
Ref |
Expression |
1 |
|
eluzelz |
|- ( N e. ( ZZ>= ` 2 ) -> N e. ZZ ) |
2 |
|
zre |
|- ( N e. ZZ -> N e. RR ) |
3 |
|
id |
|- ( N e. RR -> N e. RR ) |
4 |
|
4re |
|- 4 e. RR |
5 |
4
|
a1i |
|- ( N e. RR -> 4 e. RR ) |
6 |
|
4ne0 |
|- 4 =/= 0 |
7 |
6
|
a1i |
|- ( N e. RR -> 4 =/= 0 ) |
8 |
3 5 7
|
redivcld |
|- ( N e. RR -> ( N / 4 ) e. RR ) |
9 |
2 8
|
syl |
|- ( N e. ZZ -> ( N / 4 ) e. RR ) |
10 |
|
flle |
|- ( ( N / 4 ) e. RR -> ( |_ ` ( N / 4 ) ) <_ ( N / 4 ) ) |
11 |
1 9 10
|
3syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( |_ ` ( N / 4 ) ) <_ ( N / 4 ) ) |
12 |
|
1red |
|- ( N e. ( ZZ>= ` 2 ) -> 1 e. RR ) |
13 |
|
eluzelre |
|- ( N e. ( ZZ>= ` 2 ) -> N e. RR ) |
14 |
|
rehalfcl |
|- ( N e. RR -> ( N / 2 ) e. RR ) |
15 |
1 2 14
|
3syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( N / 2 ) e. RR ) |
16 |
|
2rp |
|- 2 e. RR+ |
17 |
16
|
a1i |
|- ( N e. ( ZZ>= ` 2 ) -> 2 e. RR+ ) |
18 |
|
eluzle |
|- ( N e. ( ZZ>= ` 2 ) -> 2 <_ N ) |
19 |
|
divge1 |
|- ( ( 2 e. RR+ /\ N e. RR /\ 2 <_ N ) -> 1 <_ ( N / 2 ) ) |
20 |
17 13 18 19
|
syl3anc |
|- ( N e. ( ZZ>= ` 2 ) -> 1 <_ ( N / 2 ) ) |
21 |
|
eluzelcn |
|- ( N e. ( ZZ>= ` 2 ) -> N e. CC ) |
22 |
|
subhalfhalf |
|- ( N e. CC -> ( N - ( N / 2 ) ) = ( N / 2 ) ) |
23 |
21 22
|
syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( N - ( N / 2 ) ) = ( N / 2 ) ) |
24 |
20 23
|
breqtrrd |
|- ( N e. ( ZZ>= ` 2 ) -> 1 <_ ( N - ( N / 2 ) ) ) |
25 |
12 13 15 24
|
lesubd |
|- ( N e. ( ZZ>= ` 2 ) -> ( N / 2 ) <_ ( N - 1 ) ) |
26 |
|
2t2e4 |
|- ( 2 x. 2 ) = 4 |
27 |
26
|
eqcomi |
|- 4 = ( 2 x. 2 ) |
28 |
27
|
a1i |
|- ( N e. ( ZZ>= ` 2 ) -> 4 = ( 2 x. 2 ) ) |
29 |
28
|
oveq2d |
|- ( N e. ( ZZ>= ` 2 ) -> ( N / 4 ) = ( N / ( 2 x. 2 ) ) ) |
30 |
|
2cnne0 |
|- ( 2 e. CC /\ 2 =/= 0 ) |
31 |
30
|
a1i |
|- ( N e. ( ZZ>= ` 2 ) -> ( 2 e. CC /\ 2 =/= 0 ) ) |
32 |
|
divdiv1 |
|- ( ( N e. CC /\ ( 2 e. CC /\ 2 =/= 0 ) /\ ( 2 e. CC /\ 2 =/= 0 ) ) -> ( ( N / 2 ) / 2 ) = ( N / ( 2 x. 2 ) ) ) |
33 |
21 31 31 32
|
syl3anc |
|- ( N e. ( ZZ>= ` 2 ) -> ( ( N / 2 ) / 2 ) = ( N / ( 2 x. 2 ) ) ) |
34 |
29 33
|
eqtr4d |
|- ( N e. ( ZZ>= ` 2 ) -> ( N / 4 ) = ( ( N / 2 ) / 2 ) ) |
35 |
34
|
breq1d |
|- ( N e. ( ZZ>= ` 2 ) -> ( ( N / 4 ) <_ ( ( N - 1 ) / 2 ) <-> ( ( N / 2 ) / 2 ) <_ ( ( N - 1 ) / 2 ) ) ) |
36 |
|
peano2rem |
|- ( N e. RR -> ( N - 1 ) e. RR ) |
37 |
13 36
|
syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( N - 1 ) e. RR ) |
38 |
15 37 17
|
lediv1d |
|- ( N e. ( ZZ>= ` 2 ) -> ( ( N / 2 ) <_ ( N - 1 ) <-> ( ( N / 2 ) / 2 ) <_ ( ( N - 1 ) / 2 ) ) ) |
39 |
35 38
|
bitr4d |
|- ( N e. ( ZZ>= ` 2 ) -> ( ( N / 4 ) <_ ( ( N - 1 ) / 2 ) <-> ( N / 2 ) <_ ( N - 1 ) ) ) |
40 |
25 39
|
mpbird |
|- ( N e. ( ZZ>= ` 2 ) -> ( N / 4 ) <_ ( ( N - 1 ) / 2 ) ) |
41 |
8
|
flcld |
|- ( N e. RR -> ( |_ ` ( N / 4 ) ) e. ZZ ) |
42 |
41
|
zred |
|- ( N e. RR -> ( |_ ` ( N / 4 ) ) e. RR ) |
43 |
36
|
rehalfcld |
|- ( N e. RR -> ( ( N - 1 ) / 2 ) e. RR ) |
44 |
42 8 43
|
3jca |
|- ( N e. RR -> ( ( |_ ` ( N / 4 ) ) e. RR /\ ( N / 4 ) e. RR /\ ( ( N - 1 ) / 2 ) e. RR ) ) |
45 |
1 2 44
|
3syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( ( |_ ` ( N / 4 ) ) e. RR /\ ( N / 4 ) e. RR /\ ( ( N - 1 ) / 2 ) e. RR ) ) |
46 |
|
letr |
|- ( ( ( |_ ` ( N / 4 ) ) e. RR /\ ( N / 4 ) e. RR /\ ( ( N - 1 ) / 2 ) e. RR ) -> ( ( ( |_ ` ( N / 4 ) ) <_ ( N / 4 ) /\ ( N / 4 ) <_ ( ( N - 1 ) / 2 ) ) -> ( |_ ` ( N / 4 ) ) <_ ( ( N - 1 ) / 2 ) ) ) |
47 |
45 46
|
syl |
|- ( N e. ( ZZ>= ` 2 ) -> ( ( ( |_ ` ( N / 4 ) ) <_ ( N / 4 ) /\ ( N / 4 ) <_ ( ( N - 1 ) / 2 ) ) -> ( |_ ` ( N / 4 ) ) <_ ( ( N - 1 ) / 2 ) ) ) |
48 |
11 40 47
|
mp2and |
|- ( N e. ( ZZ>= ` 2 ) -> ( |_ ` ( N / 4 ) ) <_ ( ( N - 1 ) / 2 ) ) |