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.

A193306 Number of 'Reverse and Subtract' steps needed to reach 0, or -1 if never reaches 0, using base -1+i and subtracting the reversed number from original.

Table of values

n a(n)
0 0
1 1
2 2
3 1
4 4
5 1
6 4
7 1
8 4
9 1
10 4
11 3
12 -1
13 -1
14 4
15 1
16 -1
17 1
18 4
19 -1
20 -1
21 1
22 4
23 -1
24 2
25 11
26 -1
27 1
28 2
29 11
30 -1
31 1
32 -1
33 1
34 12
35 11
36 -1
37 3
38 2
39 -1
40 6
41 -1
42 -1
43 -1
44 -1
45 1
46 12
47 11
48 4
49 -1
50 -1
51 1
52 8
53 5
54 -1
55 3
56 -1
57 3
58 6
59 -1
60 4
61 -1
62 -1
63 1
64 2
65 1
66 2
67 -1
68 -1
69 -1
70 -1
71 3
72 2
73 1
74 2

List of values

[0, 1, 2, 1, 4, 1, 4, 1, 4, 1, 4, 3, -1, -1, 4, 1, -1, 1, 4, -1, -1, 1, 4, -1, 2, 11, -1, 1, 2, 11, -1, 1, -1, 1, 12, 11, -1, 3, 2, -1, 6, -1, -1, -1, -1, 1, 12, 11, 4, -1, -1, 1, 8, 5, -1, 3, -1, 3, 6, -1, 4, -1, -1, 1, 2, 1, 2, -1, -1, -1, -1, 3, 2, 1, 2]