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.
| n | a(n) |
|---|---|
| 0 | 11 |
| 1 | 2 |
| 2 | 41 |
| 3 | 181 |
| 4 | 281 |
| 5 | 1481 |
| 6 | 881 |
| 7 | 4481 |
| 8 | 18481 |
| 9 | 48281 |
| 10 | 48481 |
| 11 | 228881 |
| 12 | 284881 |
| 13 | 828881 |
| 14 | 884881 |
| 15 | 4448881 |
| 16 | 4848881 |
| 17 | 18848881 |
| 18 | 24888881 |
| 19 | 48888841 |
| 20 | 88884881 |
| 21 | 188888881 |
| 22 | 888828881 |
| 23 | 848888881 |
| 24 | 4848488881 |
| 25 | 4488888881 |
| 26 | 18848888881 |
| 27 | 28888884881 |