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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.

A227983 Numbers n such that sigma(n+1) - sigma(n-1) < sigma(n); where sigma(n) = A000203(n) = sum of the divisors of n.

Table of values

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

List of values

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

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

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