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 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 45 |
| 5 | 186 |
| 6 | 945 |
| 7 | 5778 |
| 8 | 44037 |
| 9 | 403470 |
| 10 | 4344877 |
| 11 | 56072378 |
| 12 | 793804721 |
| 13 | 12734185106 |
| 14 | 229632768005 |
| 15 | 4628786367502 |
| 16 | 105803768420397 |
| 17 | 2626282179198138 |
| 18 | 71539181027191729 |
| 19 | 2076395667668755090 |
| 20 | 65704452165048754181 |