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 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 20 |
| 7 | 48 |
| 8 | 115 |
| 9 | 286 |
| 10 | 719 |
| 11 | 1842 |
| 12 | 4766 |
| 13 | 12486 |
| 14 | 32972 |
| 15 | 87807 |
| 16 | 235365 |
| 17 | 634792 |
| 18 | 1720976 |
| 19 | 4688090 |
| 20 | 12824381 |
| 21 | 35216108 |
| 22 | 97037603 |
| 23 | 268229329 |
| 24 | 743562936 |
| 25 | 2066686470 |
| 26 | 5758171390 |
| 27 | 16079351152 |