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.

A136904 Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 8.

Table of values

n a(n)
1 0
2 2
3 8
4 20
5 22
6 68
7 80
8 200
9 202
10 220
11 262
12 668
13 680
14 800
15 2000
16 2002
17 2020
18 2022
19 2200
20 2202
21 2620
22 6668
23 6680
24 6800
25 8000
26 8262
27 20000
28 20002
29 20020
30 20022
31 20200
32 20220
33 20602
34 22000
35 22002
36 22020
37 24622
38 26200
39 66668
40 66680
41 66800
42 68000
43 80000
44 82620
45 200000
46 200002
47 200020
48 200022
49 200200
50 200202
51 200220
52 202000
53 202002
54 202200
55 206020

List of values

[0, 2, 8, 20, 22, 68, 80, 200, 202, 220, 262, 668, 680, 800, 2000, 2002, 2020, 2022, 2200, 2202, 2620, 6668, 6680, 6800, 8000, 8262, 20000, 20002, 20020, 20022, 20200, 20220, 20602, 22000, 22002, 22020, 24622, 26200, 66668, 66680, 66800, 68000, 80000, 82620, 200000, 200002, 200020, 200022, 200200, 200202, 200220, 202000, 202002, 202200, 206020]

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

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