
150 Lattice Basis Reduction
Example 9.5. Using the method of continued fractions to find rational ap-
proximations for the square roots of the first four prime number s, we obtain
√
2 ≈
1
1
,
3
2
,
7
5
,
17
12
,
41
29
,
99
70
,
239
169
,
577
408
,
1393
985
, . . .
√
3 ≈
1
1
,
2
1
,
5
3
,
7
4
,
19
11
,
26
15
,
71
41
,
97
56
,
265
153
, . . .
√
5 ≈
2
1
,
9
4
,
38
17
,
161
72
,
682
305
,
2889
1292
,
12238
5473
,
51841
23184
,
219602
98209
, . . .
√
7 ≈
2
1
,
3
1
,
5
2
,
8
3
,
37
14
,
45
17
,
82
31
,
127
48
,
590
223
, . . .
Note that the only denominator that appears in e very list of the first 9 ap-
proximations is the trivial denominator 1.
We now consider simultaneous approximation of these four square roots.
We sta rt w ith the first rational approximation in each ...