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 | 9 |
| 2 | 46 |
| 3 | 175 |
| 4 | 551 |
| 5 | 1518 |
| 6 | 3785 |
| 7 | 8735 |
| 8 | 18955 |
| 9 | 39130 |
| 10 | 77533 |
| 11 | 148487 |
| 12 | 276408 |
| 13 | 502415 |
| 14 | 895103 |
| 15 | 1568062 |
| 16 | 2708322 |
| 17 | 4622488 |
| 18 | 7811510 |
| 19 | 13091798 |
| 20 | 21791338 |
| 21 | 36067176 |
| 22 | 59419294 |
| 23 | 97522270 |
| 24 | 159571139 |
| 25 | 260459265 |
| 26 | 424302452 |
| 27 | 690141333 |