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 | 1 |
| 4 | 3 |
| 5 | 4 |
| 6 | 12 |
| 7 | 24 |
| 8 | 66 |
| 9 | 159 |
| 10 | 444 |
| 11 | 1161 |
| 12 | 3226 |
| 13 | 8785 |
| 14 | 24453 |
| 15 | 67716 |
| 16 | 189309 |
| 17 | 528922 |
| 18 | 1484738 |
| 19 | 4172185 |
| 20 | 11756354 |
| 21 | 33174451 |
| 22 | 93795220 |
| 23 | 265565628 |
| 24 | 753060469 |
| 25 | 2138206966 |
| 26 | 6078931114 |
| 27 | 17302380313 |
| 28 | 49302121747 |
| 29 | 140627400927 |
| 30 | 401510058179 |