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 | 15 |
| 2 | 105 |
| 3 | 490 |
| 4 | 1764 |
| 5 | 5292 |
| 6 | 13860 |
| 7 | 32670 |
| 8 | 70785 |
| 9 | 143143 |
| 10 | 273273 |
| 11 | 496860 |
| 12 | 866320 |
| 13 | 1456560 |
| 14 | 2372112 |
| 15 | 3755844 |
| 16 | 5799465 |
| 17 | 8756055 |
| 18 | 12954865 |
| 19 | 18818646 |
| 20 | 26883780 |
| 21 | 37823500 |
| 22 | 52474500 |
| 23 | 71867250 |
| 24 | 97260345 |
| 25 | 130179231 |
| 26 | 172459665 |
| 27 | 226296280 |
| 28 | 294296640 |
| 29 | 379541184 |