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.

A202275 Differences between A074753 (number of integers k such that sigma(k) <= n) and A202276 (number of integers k <= n such that sigma(x) = k has no solution); sigma = A000203.

Table of values

n a(n)
1 1
2 0
3 1
4 2
5 1
6 2
7 3
8 4
9 3
10 2
11 1
12 3
13 4
14 5
15 6
16 5
17 4
18 6
19 5
20 6
21 5
22 4
23 3
24 6
25 5
26 4
27 3
28 4
29 3
30 4
31 6
32 8
33 7
34 6
35 5
36 6
37 5
38 6
39 7
40 8
41 7
42 10
43 9
44 10
45 9
46 8
47 7
48 10
49 9
50 8
51 7
52 6
53 5
54 7
55 6
56 8
57 9
58 8
59 7
60 10
61 9
62 10
63 11
64 10
65 9
66 8
67 7
68 8
69 7
70 6
71 5
72 10
73 9
74 10
75 9
76 8
77 7
78 8
79 7
80 9
81 8
82 7
83 6
84 9

List of values

[1, 0, 1, 2, 1, 2, 3, 4, 3, 2, 1, 3, 4, 5, 6, 5, 4, 6, 5, 6, 5, 4, 3, 6, 5, 4, 3, 4, 3, 4, 6, 8, 7, 6, 5, 6, 5, 6, 7, 8, 7, 10, 9, 10, 9, 8, 7, 10, 9, 8, 7, 6, 5, 7, 6, 8, 9, 8, 7, 10, 9, 10, 11, 10, 9, 8, 7, 8, 7, 6, 5, 10, 9, 10, 9, 8, 7, 8, 7, 9, 8, 7, 6, 9]

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