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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 23 |
| 7 | 66 |
| 8 | 185 |
| 9 | 586 |
| 10 | 1880 |
| 11 | 6360 |
| 12 | 21975 |
| 13 | 78230 |
| 14 | 283087 |
| 15 | 1043329 |
| 16 | 3895505 |
| 17 | 14726263 |
| 18 | 56234210 |
| 19 | 216719056 |
| 20 | 841857211 |
| 21 | 3293753840 |
| 22 | 12969219563 |