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 | 5 |
| 5 | 16 |
| 6 | 57 |
| 7 | 232 |
| 8 | 1017 |
| 9 | 4864 |
| 10 | 24641 |
| 11 | 133024 |
| 12 | 752765 |
| 13 | 4476928 |
| 14 | 27707513 |
| 15 | 178613376 |
| 16 | 1191756593 |
| 17 | 8231124992 |
| 18 | 58598528065 |
| 19 | 429868937728 |
| 20 | 3239768599221 |
| 21 | 25073052286976 |
| 22 | 198825601967609 |
| 23 | 1614604933769216 |
| 24 | 13405327061690025 |
| 25 | 113725655719346176 |