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 | 4 |
| 2 | 13 |
| 3 | 36 |
| 4 | 90 |
| 5 | 212 |
| 6 | 478 |
| 7 | 1044 |
| 8 | 2227 |
| 9 | 4664 |
| 10 | 9627 |
| 11 | 19640 |
| 12 | 39684 |
| 13 | 79544 |
| 14 | 158364 |
| 15 | 313464 |
| 16 | 617365 |
| 17 | 1210588 |
| 18 | 2364713 |
| 19 | 4603388 |
| 20 | 8934142 |
| 21 | 17291756 |
| 22 | 33385018 |
| 23 | 64311660 |
| 24 | 123634471 |
| 25 | 237233712 |
| 26 | 454429239 |
| 27 | 869095472 |
| 28 | 1659708488 |