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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.

A365398 Length of the longest subsequence of 1, ..., n on which sigma, the sum of the divisors of n (A000203), is nondecreasing.

Table of values

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

List of values

[1, 2, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 9, 10, 10, 11, 11, 12, 12, 12, 12, 13, 13, 13, 13, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 17, 17, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19, 19, 19, 20, 20, 21, 21, 21, 21, 22, 22, 22, 23, 24, 24, 25, 25, 25]

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

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