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.

A250221 Least k such that A_n(k) = n, or -1 if no such k exists.

Table of values

n a(n)
1 1
2 2
3 11
4 -1
5 16
6 12
7 -1
8 9
9 -1
10 11
11 -1
12 -1
13 -1
14 11
15 -1
16 8
17 -1
18 -1
19 126
20 -1
21 -1
22 -1
23 -1
24 -1
25 -1
26 26
27 27
28 -1
29 -1
30 -1
31 -1
32 -1
33 -1
34 -1
35 -1
36 29
37 31
38 -1
39 -1
40 -1
41 -1
42 -1
43 -1
44 -1
45 -1
46 -1
47 -1
48 -1
49 -1
50 -1
51 -1
52 33
53 -1
54 -1
55 -1
56 -1
57 -1
58 -1
59 19
60 -1
61 -1
62 45
63 -1
64 -1
65 -1
66 -1
67 -1
68 -1
69 35
70 -1
71 -1
72 8

List of values

[1, 2, 11, -1, 16, 12, -1, 9, -1, 11, -1, -1, -1, 11, -1, 8, -1, -1, 126, -1, -1, -1, -1, -1, -1, 26, 27, -1, -1, -1, -1, -1, -1, -1, -1, 29, 31, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 33, -1, -1, -1, -1, -1, -1, 19, -1, -1, 45, -1, -1, -1, -1, -1, -1, 35, -1, -1, 8]