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.

A067781 Numbers k such that phi(k) and sigma(k) are both perfect squares.

Table of values

n a(n)
1 1
2 170
3 364
4 679
5 5044
6 5130
7 5670
8 5770
9 8721
10 8736
11 9154
12 9639
13 9809
14 14322
15 16376
16 22413
17 27783
18 30256
19 32025
20 37114
21 38760
22 51455
23 71604
24 78570
25 82615
26 88392
27 92004
28 100821
29 101153
30 104168
31 115430
32 121056
33 133569
34 139954
35 148568
36 171069
37 177940
38 198462
39 217868

List of values

[1, 170, 364, 679, 5044, 5130, 5670, 5770, 8721, 8736, 9154, 9639, 9809, 14322, 16376, 22413, 27783, 30256, 32025, 37114, 38760, 51455, 71604, 78570, 82615, 88392, 92004, 100821, 101153, 104168, 115430, 121056, 133569, 139954, 148568, 171069, 177940, 198462, 217868]

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

Content is available under The OEIS End-User License Agreement.