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 | 3 |
| 4 | 12 |
| 5 | 56 |
| 6 | 289 |
| 7 | 1603 |
| 8 | 9391 |
| 9 | 57437 |
| 10 | 363773 |
| 11 | 2371551 |
| 12 | 15842850 |
| 13 | 108070370 |
| 14 | 750655459 |
| 15 | 5297314241 |
| 16 | 37909476912 |
| 17 | 274693258884 |
| 18 | 2012767854337 |
| 19 | 14897269924571 |
| 20 | 111269729060260 |
| 21 | 838012360130944 |
| 22 | 6359434553977763 |
| 23 | 48597188639038769 |
| 24 | 373757879279966501 |