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 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 42 |
| 4 | 246 |
| 5 | 1435 |
| 6 | 8365 |
| 7 | 48756 |
| 8 | 284172 |
| 9 | 1656277 |
| 10 | 9653491 |
| 11 | 56264670 |
| 12 | 327934530 |
| 13 | 1911342511 |
| 14 | 11140120537 |
| 15 | 64929380712 |
| 16 | 378436163736 |
| 17 | 2205687601705 |
| 18 | 12855689446495 |
| 19 | 74928449077266 |
| 20 | 436715005017102 |
| 21 | 2545361581025347 |
| 22 | 14835454481134981 |
| 23 | 86467365305784540 |