cp's OEIS Frontend

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.

A246922 Irregular triangular array: every periodic simple continued fraction CF represents a quadratic irrational (c + f*sqrt(d))/b, where b,c,f,d are integers and d is squarefree. Row n of this array shows the distinct values of d as CF ranges through the periodic continued fractions having period an n-tuple of 1s and 3s.

Table of values

n a(n)
1 5
2 13
3 5
4 13
5 21
6 5
7 13
8 17
9 65
10 5
11 13
12 21
13 29
14 165
15 2805
16 5
17 13
18 61
19 317
20 445
21 1853
22 5933
23 30629
24 2
25 5
26 7
27 13
28 15
29 17
30 21
31 34
32 35
33 65
34 66
35 145
36 5402
37 5
38 13
39 3029
40 10205
41 11029
42 12773
43 28157
44 34973
45 42853
46 47965
47 53365
48 136165
49 184045
50 187493
51 219965
52 724205

List of values

[5, 13, 5, 13, 21, 5, 13, 17, 65, 5, 13, 21, 29, 165, 2805, 5, 13, 61, 317, 445, 1853, 5933, 30629, 2, 5, 7, 13, 15, 17, 21, 34, 35, 65, 66, 145, 5402, 5, 13, 3029, 10205, 11029, 12773, 28157, 34973, 42853, 47965, 53365, 136165, 184045, 187493, 219965, 724205]

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

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