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 | 3 |
| 5 | 6 |
| 6 | 13 |
| 7 | 30 |
| 8 | 76 |
| 9 | 220 |
| 10 | 700 |
| 11 | 2520 |
| 12 | 10503 |
| 13 | 51368 |
| 14 | 306328 |
| 15 | 2313432 |
| 16 | 23069977 |
| 17 | 314605256 |
| 18 | 5991456377 |
| 19 | 160321885780 |
| 20 | 6008649072476 |
| 21 | 313490988938680 |
| 22 | 22641945794083024 |
| 23 | 2254587340059129076 |
| 24 | 308683056074116543631 |