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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A020440 Numbers k such that the period of the continued fraction for sqrt(k) contains exactly four 1's.

Table of values

n a(n)
1 13
2 21
3 31
4 57
5 61
6 67
7 73
8 74
9 92
10 106
11 108
12 109
13 111
14 112
15 116
16 129
17 137
18 158
19 161
20 162
21 183
22 185
23 193
24 204
25 207
26 236
27 237
28 243
29 246
30 251
31 261
32 262
33 265
34 273
35 274
36 275
37 282
38 297
39 298
40 308
41 314
42 317
43 329
44 332
45 341
46 346
47 351
48 355
49 364
50 375
51 381
52 383
53 384
54 388
55 406
56 412

List of values

[13, 21, 31, 57, 61, 67, 73, 74, 92, 106, 108, 109, 111, 112, 116, 129, 137, 158, 161, 162, 183, 185, 193, 204, 207, 236, 237, 243, 246, 251, 261, 262, 265, 273, 274, 275, 282, 297, 298, 308, 314, 317, 329, 332, 341, 346, 351, 355, 364, 375, 381, 383, 384, 388, 406, 412]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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