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 | 19 |
| 3 | 123 |
| 4 | 275 |
| 5 | 1915 |
| 6 | 4627 |
| 7 | 32379 |
| 8 | 67347 |
| 9 | 463739 |
| 10 | 1276435 |
| 11 | 8001147 |
| 12 | 18245395 |
| 13 | 124220283 |
| 14 | 309475859 |
| 15 | 2134808187 |
| 16 | 4354074387 |
| 17 | 30225757051 |
| 18 | 82642024979 |
| 19 | 530573137531 |
| 20 | 1175676118803 |
| 21 | 8199373878139 |
| 22 | 19977819994643 |
| 23 | 139441424012923 |
| 24 | 286691477808915 |