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.

A188621 Smallest number k>1 such that k*(n-th triangular number) is also a triangular number.

Table of values

n a(n)
1 3
2 2
3 6
4 12
5 3
6 5
7 42
8 56
9 14
10 18
11 8
12 10
13 33
14 2
15 27
16 240
17 60
18 68
19 15
20 3
21 13
22 105
23 61
24 67
25 138
26 150
27 47
28 51
29 24
30 26
31 930
32 117
33 21
34 6
35 40
36 66
37 315
38 41
39 7
40 231
41 35
42 37
43 118
44 5
45 83
46 495
47 220
48 230
49 564
50 55
51 28
52 147
53 663
54 98
55 10
56 50
57 92
58 798
59 221
60 229
61 885
62 12
63 741
64 615

List of values

[3, 2, 6, 12, 3, 5, 42, 56, 14, 18, 8, 10, 33, 2, 27, 240, 60, 68, 15, 3, 13, 105, 61, 67, 138, 150, 47, 51, 24, 26, 930, 117, 21, 6, 40, 66, 315, 41, 7, 231, 35, 37, 118, 5, 83, 495, 220, 230, 564, 55, 28, 147, 663, 98, 10, 50, 92, 798, 221, 229, 885, 12, 741, 615]

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

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