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 | 6 |
| 2 | 27 |
| 3 | 104 |
| 4 | 363 |
| 5 | 1182 |
| 6 | 3653 |
| 7 | 10836 |
| 8 | 31092 |
| 9 | 86784 |
| 10 | 236640 |
| 11 | 632448 |
| 12 | 1661056 |
| 13 | 4296192 |
| 14 | 10961664 |
| 15 | 27630592 |
| 16 | 68889600 |
| 17 | 170065920 |
| 18 | 416071680 |
| 19 | 1009582080 |
| 20 | 2431254528 |
| 21 | 5814222848 |
| 22 | 13815054336 |
| 23 | 32629850112 |
| 24 | 76640681984 |
| 25 | 179080003584 |
| 26 | 416412598272 |
| 27 | 963876225024 |