PlanetMath (more info)
 Math for the people, by the people.
Encyclopedia | Requests | Forums | Docs | Wiki | Random | RSS  
Login
create new user
name:
pass:
forget your password?
Main Menu
Owner confidence rating: Very high Entry average rating: Very high
[parent] table of continued fractions of $\sqrt{n}$ for $1 < n < 102$ (Data Structure)

The simple continued fractions for the square roots of positive integers (which aren't perfect powers) are non-terminating but they are periodic. In the following table, the square roots of the integers from 2 to 101 (excluding perfect powers) are listed in compact form: first the integer part followed by semicolon, then the periodic part stated once, its individual terms separated by commas. For example, the notation “14; 14, 28” for 198 means

$\displaystyle \sqrt{198} = 14 + \frac{1}{14 + \frac{1}{28 + \frac{1}{14 + \frac{1}{28 + \ldots}}}},$
where the dots mean a periodic repetition of 14 and 28 in the denominators.
$ n$ Continued fraction of $ \sqrt{n}$
2 1; 2
3 1; 1, 2
5 2; 4
6 2; 2, 4
7 2; 1, 1, 1, 4
8 2; 1, 4
10 3; 6
11 3; 3, 6
12 3; 2, 6
13 3; 1, 1, 1, 1, 6
14 3; 1, 2, 1, 6
15 3; 1, 6
17 4; 8
18 4; 4, 8
19 4; 2, 1, 3, 1, 2, 8
20 4; 2, 8
21 4; 1, 1, 2, 1, 1, 8
22 4; 1, 2, 4, 2, 1, 8
23 4; 1, 3, 1, 8
24 4; 1, 8
26 5; 10
27 5; 5, 10
28 5; 3, 2, 3, 10
29 5; 2, 1, 1, 2, 10
30 5; 2, 10
31 5; 1, 1, 3, 5, 3, 1, 1, 10
32 5; 1, 1, 1, 10
33 5; 1, 2, 1, 10
34 5; 1, 4, 1, 10
35 5; 1, 10
37 6; 12
38 6; 6, 12
39 6; 4, 12
40 6; 3, 12
41 6; 2, 2, 12
42 6; 2, 12
43 6; 1, 1, 3, 1, 5, 1, 3, 1, 1, 12
44 6; 1, 1, 1, 2, 1, 1, 1, 12
45 6; 1, 2, 2, 2, 1, 12
46 6; 1, 3, 1, 1, 2, 6, 2, 1, 1, 3, 1, 12
47 6; 1, 5, 1, 12
48 6; 1, 12
50 7; 14
51 7; 7, 14
52 7; 4, 1, 2, 1, 4, 14
53 7; 3, 1, 1, 3, 14
54 7; 2, 1, 6, 1, 2, 14
55 7; 2, 2, 2, 14
56 7; 2, 14
57 7; 1, 1, 4, 1, 1, 14
58 7; 1, 1, 1, 1, 1, 1, 14
59 7; 1, 2, 7, 2, 1, 14
60 7; 1, 2, 1, 14
61 7; 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14
62 7; 1, 6, 1, 14
63 7; 1, 14
65 8; 16
66 8; 8, 16
67 8; 5, 2, 1, 1, 7, 1, 1, 2, 5, 16
68 8; 4, 16
69 8; 3, 3, 1, 4, 1, 3, 3, 16
70 8; 2, 1, 2, 1, 2, 16
71 8; 2, 2, 1, 7, 1, 2, 2, 16
72 8; 2, 16
73 8; 1, 1, 5, 5, 1, 1, 16
74 8; 1, 1, 1, 1, 16
75 8; 1, 1, 1, 16
76 8; 1, 2, 1, 1, 5, 4, 5, 1, 1, 2, 1, 16
77 8; 1, 3, 2, 3, 1, 16
78 8; 1, 4, 1, 16
79 8; 1, 7, 1, 16
80 8; 1, 16
82 9; 18
83 9; 9, 18
84 9; 6, 18
85 9; 4, 1, 1, 4, 18
86 9; 3, 1, 1, 1, 8, 1, 1, 1, 3, 18
87 9; 3, 18
88 9; 2, 1, 1, 1, 2, 18
89 9; 2, 3, 3, 2, 18
90 9; 2, 18
91 9; 1, 1, 5, 1, 5, 1, 1, 18
92 9; 1, 1, 2, 4, 2, 1, 1, 18
93 9; 1, 1, 1, 4, 6, 4, 1, 1, 1, 18
94 9; 1, 2, 3, 1, 1, 5, 1, 8, 1, 5, 1, 1, 3, 2, 1, 18
95 9; 1, 2, 1, 18
96 9; 1, 3, 1, 18
97 9; 1, 5, 1, 1, 1, 1, 1, 1, 5, 1, 18
98 9; 1, 8, 1, 18
99 9; 1, 18
101 10; 20

As the table shows, the periodic part ends with $ 2 \lfloor \sqrt{n} \rfloor$.



"table of continued fractions of $\sqrt{n}$ for $1 < n < 102$" is owned by PrimeFan.
(view preamble)

View style:


This object's parent.
Log in to rate this entry.
(view current ratings)

Cross-references: continued fraction, denominators, mean, separated, terms, integer part, compact, periodic, perfect, integers, positive, square roots, simple continued fractions

This is version 1 of table of continued fractions of $\sqrt{n}$ for $1 < n < 102$, born on 2007-08-26.
Object id is 9896, canonical name is TableOfContinuedFractionsOfSqrtnFor1N102.
Accessed 484 times total.

Classification:
AMS MSC11A25 (Number theory :: Elementary number theory :: Arithmetic functions; related numbers; inversion formulas)

Pending Errata and Addenda
None.
Discussion
Style: Expand: Order:
forum policy
"End" of periodic part of continued fractions of square roots by Mravinci on 2007-08-27 16:32:10
"As the table shows, the periodic part ends with $2 \lfloor \sqrt{n} \rfloor$."

Interesting. So the continued fraction of sqrt(n^2 + 1) is always of the form n; 2n. Why is this?
[ reply | up ]

Interact
post | correct | update request | add example | add (any)