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.

A340531 Irregular triangle read by rows T(n,k), (n >= 1, k >= 1), in which row n has length is A000070(n-1) and every column k is A024916, the sum of all divisors of all numbers <= n.

Table of values

n a(n)
1 1
2 4
3 1
4 8
5 4
6 1
7 1
8 15
9 8
10 4
11 4
12 1
13 1
14 1
15 21
16 15
17 8
18 8
19 4
20 4
21 4
22 1
23 1
24 1
25 1
26 1
27 33
28 21
29 15
30 15
31 8
32 8
33 8
34 4
35 4
36 4
37 4
38 4
39 1
40 1
41 1
42 1
43 1
44 1
45 1
46 41
47 33
48 21
49 21
50 15
51 15
52 15
53 8
54 8
55 8
56 8
57 8
58 4
59 4
60 4
61 4
62 4
63 4
64 4
65 1
66 1
67 1
68 1
69 1
70 1
71 1
72 1
73 1
74 1
75 1
76 56
77 41
78 33
79 33
80 21
81 21
82 21
83 15
84 15
85 15
86 15
87 15

List of values

[1, 4, 1, 8, 4, 1, 1, 15, 8, 4, 4, 1, 1, 1, 21, 15, 8, 8, 4, 4, 4, 1, 1, 1, 1, 1, 33, 21, 15, 15, 8, 8, 8, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 41, 33, 21, 21, 15, 15, 15, 8, 8, 8, 8, 8, 4, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 56, 41, 33, 33, 21, 21, 21, 15, 15, 15, 15, 15]