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.

A114209 Number of permutations of [n] having exactly two fixed points and avoiding the patterns 123 and 231.

Table of values

n a(n)
1 0
2 1
3 0
4 2
5 1
6 3
7 2
8 5
9 3
10 7
11 5
12 9
13 7
14 12
15 9
16 15
17 12
18 18
19 15
20 22
21 18
22 26
23 22
24 30
25 26
26 35
27 30
28 40
29 35
30 45
31 40
32 51
33 45
34 57
35 51
36 63
37 57
38 70
39 63
40 77
41 70
42 84
43 77
44 92
45 84
46 100
47 92
48 108
49 100
50 117
51 108
52 126
53 117
54 135
55 126
56 145
57 135
58 155
59 145
60 165
61 155
62 176
63 165
64 187
65 176
66 198
67 187

List of values

[0, 1, 0, 2, 1, 3, 2, 5, 3, 7, 5, 9, 7, 12, 9, 15, 12, 18, 15, 22, 18, 26, 22, 30, 26, 35, 30, 40, 35, 45, 40, 51, 45, 57, 51, 63, 57, 70, 63, 77, 70, 84, 77, 92, 84, 100, 92, 108, 100, 117, 108, 126, 117, 135, 126, 145, 135, 155, 145, 165, 155, 176, 165, 187, 176, 198, 187]

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

Content is available under The OEIS End-User License Agreement.