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 | 1 |
| 1 | 7 |
| 2 | 27 |
| 3 | 104 |
| 4 | 378 |
| 5 | 1327 |
| 6 | 4553 |
| 7 | 15351 |
| 8 | 51072 |
| 9 | 168147 |
| 10 | 548915 |
| 11 | 1779377 |
| 12 | 5734022 |
| 13 | 18384612 |
| 14 | 58688163 |
| 15 | 186632570 |
| 16 | 591509670 |
| 17 | 1869118923 |
| 18 | 5890466415 |
| 19 | 18518945789 |
| 20 | 58094637801 |
| 21 | 181884111404 |
| 22 | 568416743474 |
| 23 | 1773443888599 |